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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master

Details
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http://git.postgresql.org/pg/commitdiff/f3839ea117fba6fdb69c75a1fe145aa86a4c8ae3

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(-)