pgsql: Bring syntax of role-related commands into SQL compliance.

Log Message:
-----------
Bring syntax of role-related commands into SQL compliance. To avoid
syntactic conflicts, both privilege and role GRANT/REVOKE commands have
to use the same production for scanning the list of tokens that might
eventually turn out to be privileges or role names. So, change the
existing GRANT/REVOKE code to expect a list of strings not pre-reduced
AclMode values. Fix a couple other minor issues while at it, such as
InitializeAcl function name conflicting with a Windows system function.

Modified Files:
--------------
pgsql/src/backend/catalog:
aclchk.c (r1.113 -> r1.114)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/aclchk.c.diff?r1=1.113&r2=1.114)
pg_proc.c (r1.130 -> r1.131)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/catalog/pg_proc.c.diff?r1=1.130&r2=1.131)
pgsql/src/backend/commands:
user.c (r1.152 -> r1.153)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/commands/user.c.diff?r1=1.152&r2=1.153)
pgsql/src/backend/parser:
gram.y (r2.499 -> r2.500)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/gram.y.diff?r1=2.499&r2=2.500)
keywords.c (r1.160 -> r1.161)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/parser/keywords.c.diff?r1=1.160&r2=1.161)
pgsql/src/backend/utils/adt:
acl.c (r1.115 -> r1.116)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/adt/acl.c.diff?r1=1.115&r2=1.116)
pgsql/src/backend/utils/init:
postinit.c (r1.150 -> r1.151)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/backend/utils/init/postinit.c.diff?r1=1.150&r2=1.151)
pgsql/src/include/nodes:
parsenodes.h (r1.284 -> r1.285)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/nodes/parsenodes.h.diff?r1=1.284&r2=1.285)
pgsql/src/include/storage:
pmsignal.h (r1.11 -> r1.12)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/storage/pmsignal.h.diff?r1=1.11&r2=1.12)
pgsql/src/include/utils:
acl.h (r1.78 -> r1.79)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/include/utils/acl.h.diff?r1=1.78&r2=1.79)
pgsql/src/test/regress/expected:
rules.out (r1.103 -> r1.104)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/src/test/regress/expected/rules.out.diff?r1=1.103&r2=1.104)