pgsql: Remove ALTER DEFAULT PRIVILEGES' requirement of schema CREATE pe

Remove ALTER DEFAULT PRIVILEGES' requirement of schema CREATE permissions.

Per discussion, this restriction isn't needed for any real security reason,
and it seems to confuse people more often than it helps them.  It could
also result in some database states being unrestorable.  So just drop it.

Back-patch to 9.0, where ALTER DEFAULT PRIVILEGES was introduced.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/aee8a60c7232cc048e00a704fca49730a722432a

Modified Files
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doc/src/sgml/ref/alter_default_privileges.sgml |    4 ++--
src/backend/catalog/aclchk.c                   |   25 ++++++++++++------------
2 files changed, 14 insertions(+), 15 deletions(-)