pgsql: Make pg_stat_activity.application_name visible to all users,

Log Message:
-----------
Make pg_stat_activity.application_name visible to all users, rather than
being hidden when current_query is. Relocate it to a column position
more consistent with that behavior. Per discussion.

Modified Files:
--------------
pgsql/doc/src/sgml:
monitoring.sgml (r1.72 -> r1.73)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/monitoring.sgml?r1=1.72&r2=1.73)
pgsql/src/backend/catalog:
system_views.sql (r1.62 -> r1.63)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/system_views.sql?r1=1.62&r2=1.63)
pgsql/src/backend/utils/adt:
pgstatfuncs.c (r1.55 -> r1.56)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/pgstatfuncs.c?r1=1.55&r2=1.56)
pgsql/src/include/catalog:
catversion.h (r1.553 -> r1.554)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/catversion.h?r1=1.553&r2=1.554)
pg_proc.h (r1.553 -> r1.554)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/include/catalog/pg_proc.h?r1=1.553&r2=1.554)
pgsql/src/test/regress/expected:
rules.out (r1.152 -> r1.153)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/rules.out?r1=1.152&r2=1.153)