Remove ancient (and badly written) check for aclocal/automake, and
replace a deprecated macro in configure.ac.in.
Handle default privileges to PUBLIC correctly.

Teach pgObject::GetGrant() that databases, functions and languages
have implicit privileges granted to PUBLIC, and that REVOKE statements
may need to be generated for them.

Ensure that affected object properties dialogues display the default
privileges so the user can revoke them if desired.
Update CHANGELOG for "Handle default privileges to PUBLIC correctly."
Merge remote branch 'origin/master' into debugger_redesign