pgsql: Update reference documentation on may/can/might: Standard

Log Message:
-----------
Update reference documentation on may/can/might:

Standard English uses "may", "can", and "might" in different ways:

may - permission, "You may borrow my rake."

can - ability, "I can lift that log."

might - possibility, "It might rain today."

Unfortunately, in conversational English, their use is often mixed, as
in, "You may use this variable to do X", when in fact, "can" is a better
choice. Similarly, "It may crash" is better stated, "It might crash".

Modified Files:
--------------
pgsql/doc/src/sgml/ref:
alter_domain.sgml (r1.20 -> r1.21)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_domain.sgml.diff?r1=1.20&r2=1.21)
alter_index.sgml (r1.11 -> r1.12)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_index.sgml.diff?r1=1.11&r2=1.12)
alter_opfamily.sgml (r1.1 -> r1.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_opfamily.sgml.diff?r1=1.1&r2=1.2)
alter_sequence.sgml (r1.15 -> r1.16)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_sequence.sgml.diff?r1=1.15&r2=1.16)
alter_table.sgml (r1.92 -> r1.93)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/alter_table.sgml.diff?r1=1.92&r2=1.93)
analyze.sgml (r1.20 -> r1.21)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/analyze.sgml.diff?r1=1.20&r2=1.21)
begin.sgml (r1.34 -> r1.35)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/begin.sgml.diff?r1=1.34&r2=1.35)
checkpoint.sgml (r1.14 -> r1.15)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/checkpoint.sgml.diff?r1=1.14&r2=1.15)
cluster.sgml (r1.38 -> r1.39)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/cluster.sgml.diff?r1=1.38&r2=1.39)
comment.sgml (r1.34 -> r1.35)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/comment.sgml.diff?r1=1.34&r2=1.35)
copy.sgml (r1.77 -> r1.78)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/copy.sgml.diff?r1=1.77&r2=1.78)
create_aggregate.sgml (r1.36 -> r1.37)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_aggregate.sgml.diff?r1=1.36&r2=1.37)
create_cast.sgml (r1.23 -> r1.24)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_cast.sgml.diff?r1=1.23&r2=1.24)
create_conversion.sgml (r1.18 -> r1.19)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_conversion.sgml.diff?r1=1.18&r2=1.19)
create_database.sgml (r1.46 -> r1.47)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_database.sgml.diff?r1=1.46&r2=1.47)
create_domain.sgml (r1.29 -> r1.30)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_domain.sgml.diff?r1=1.29&r2=1.30)
create_function.sgml (r1.71 -> r1.72)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_function.sgml.diff?r1=1.71&r2=1.72)
create_index.sgml (r1.59 -> r1.60)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_index.sgml.diff?r1=1.59&r2=1.60)
create_language.sgml (r1.42 -> r1.43)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_language.sgml.diff?r1=1.42&r2=1.43)
create_opclass.sgml (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_opclass.sgml.diff?r1=1.19&r2=1.20)
create_operator.sgml (r1.46 -> r1.47)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_operator.sgml.diff?r1=1.46&r2=1.47)
create_opfamily.sgml (r1.1 -> r1.2)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_opfamily.sgml.diff?r1=1.1&r2=1.2)
create_role.sgml (r1.8 -> r1.9)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_role.sgml.diff?r1=1.8&r2=1.9)
create_rule.sgml (r1.48 -> r1.49)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_rule.sgml.diff?r1=1.48&r2=1.49)
create_schema.sgml (r1.18 -> r1.19)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_schema.sgml.diff?r1=1.18&r2=1.19)
create_sequence.sgml (r1.45 -> r1.46)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_sequence.sgml.diff?r1=1.45&r2=1.46)
create_table.sgml (r1.105 -> r1.106)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_table.sgml.diff?r1=1.105&r2=1.106)
create_tablespace.sgml (r1.7 -> r1.8)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_tablespace.sgml.diff?r1=1.7&r2=1.8)
create_trigger.sgml (r1.45 -> r1.46)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_trigger.sgml.diff?r1=1.45&r2=1.46)
create_type.sgml (r1.66 -> r1.67)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_type.sgml.diff?r1=1.66&r2=1.67)
create_view.sgml (r1.33 -> r1.34)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/create_view.sgml.diff?r1=1.33&r2=1.34)
declare.sgml (r1.39 -> r1.40)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/declare.sgml.diff?r1=1.39&r2=1.40)
delete.sgml (r1.28 -> r1.29)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/delete.sgml.diff?r1=1.28&r2=1.29)
drop_conversion.sgml (r1.10 -> r1.11)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_conversion.sgml.diff?r1=1.10&r2=1.11)
drop_function.sgml (r1.32 -> r1.33)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_function.sgml.diff?r1=1.32&r2=1.33)
drop_language.sgml (r1.23 -> r1.24)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_language.sgml.diff?r1=1.23&r2=1.24)
drop_opclass.sgml (r1.11 -> r1.12)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_opclass.sgml.diff?r1=1.11&r2=1.12)
drop_owned.sgml (r1.4 -> r1.5)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_owned.sgml.diff?r1=1.4&r2=1.5)
drop_table.sgml (r1.25 -> r1.26)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_table.sgml.diff?r1=1.25&r2=1.26)
drop_tablespace.sgml (r1.5 -> r1.6)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/drop_tablespace.sgml.diff?r1=1.5&r2=1.6)
ecpg-ref.sgml (r1.31 -> r1.32)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/ecpg-ref.sgml.diff?r1=1.31&r2=1.32)
explain.sgml (r1.38 -> r1.39)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/explain.sgml.diff?r1=1.38&r2=1.39)
grant.sgml (r1.62 -> r1.63)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/grant.sgml.diff?r1=1.62&r2=1.63)
initdb.sgml (r1.38 -> r1.39)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/initdb.sgml.diff?r1=1.38&r2=1.39)
insert.sgml (r1.34 -> r1.35)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/insert.sgml.diff?r1=1.34&r2=1.35)
ipcclean.sgml (r1.13 -> r1.14)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/ipcclean.sgml.diff?r1=1.13&r2=1.14)
load.sgml (r1.23 -> r1.24)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/load.sgml.diff?r1=1.23&r2=1.24)
notify.sgml (r1.28 -> r1.29)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/notify.sgml.diff?r1=1.28&r2=1.29)
pg_config-ref.sgml (r1.25 -> r1.26)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_config-ref.sgml.diff?r1=1.25&r2=1.26)
pg_controldata.sgml (r1.8 -> r1.9)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_controldata.sgml.diff?r1=1.8&r2=1.9)
pg_ctl-ref.sgml (r1.37 -> r1.38)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_ctl-ref.sgml.diff?r1=1.37&r2=1.38)
pg_dump.sgml (r1.92 -> r1.93)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_dump.sgml.diff?r1=1.92&r2=1.93)
pg_dumpall.sgml (r1.63 -> r1.64)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_dumpall.sgml.diff?r1=1.63&r2=1.64)
pg_resetxlog.sgml (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_resetxlog.sgml.diff?r1=1.19&r2=1.20)
pg_restore.sgml (r1.64 -> r1.65)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/pg_restore.sgml.diff?r1=1.64&r2=1.65)
postgres-ref.sgml (r1.48 -> r1.49)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/postgres-ref.sgml.diff?r1=1.48&r2=1.49)
prepare.sgml (r1.21 -> r1.22)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/prepare.sgml.diff?r1=1.21&r2=1.22)
psql-ref.sgml (r1.180 -> r1.181)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/psql-ref.sgml.diff?r1=1.180&r2=1.181)
reindex.sgml (r1.35 -> r1.36)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/reindex.sgml.diff?r1=1.35&r2=1.36)
release_savepoint.sgml (r1.6 -> r1.7)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/release_savepoint.sgml.diff?r1=1.6&r2=1.7)
revoke.sgml (r1.41 -> r1.42)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/revoke.sgml.diff?r1=1.41&r2=1.42)
select.sgml (r1.96 -> r1.97)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/select.sgml.diff?r1=1.96&r2=1.97)
set_role.sgml (r1.3 -> r1.4)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/set_role.sgml.diff?r1=1.3&r2=1.4)
set_session_auth.sgml (r1.15 -> r1.16)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/set_session_auth.sgml.diff?r1=1.15&r2=1.16)
start_transaction.sgml (r1.15 -> r1.16)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/start_transaction.sgml.diff?r1=1.15&r2=1.16)
truncate.sgml (r1.21 -> r1.22)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/truncate.sgml.diff?r1=1.21&r2=1.22)
unlisten.sgml (r1.28 -> r1.29)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/unlisten.sgml.diff?r1=1.28&r2=1.29)
update.sgml (r1.41 -> r1.42)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/update.sgml.diff?r1=1.41&r2=1.42)
vacuum.sgml (r1.46 -> r1.47)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/vacuum.sgml.diff?r1=1.46&r2=1.47)
vacuumdb.sgml (r1.37 -> r1.38)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/vacuumdb.sgml.diff?r1=1.37&r2=1.38)
values.sgml (r1.2 -> r1.3)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/ref/values.sgml.diff?r1=1.2&r2=1.3)