Re: CATUPDATE confusion?

Given this discussion, I have attached a patch that removes CATUPDATE for review/discussion.

One of the interesting behaviors (or perhaps not) is how 'pg_class_aclmask' handles an invalid role id when checking permissions against 'rolsuper' instead of 'rolcatupdate'.  This is demonstrated by the 'has_table_privilege' regression test expected results.  In summary, 'has_rolcatupdate' raises an error when an invalid OID is provided, however, as documented in the source 'superuser_arg' does not, simply returning false.  Therefore, when checking for superuser-ness of an non-existent role, the result will be false and not an error.  Perhaps this is OK, but my concern would be on the expected behavior around items like 'has_table_privilege'.  My natural thought would be that we would want to preserve that specific functionality, though short of adding a 'has_rolsuper' function that will raise an appropriate error, I'm uncertain of an approach.  Thoughts?