fix a memory leak in ext/gdbm
delete trailing white spaces in ext/gdbm
fix type in ext/gdbm
make GDBM#index warn like Hash
update rdoc in ext/gdbm
change the method declaration in ext/gdbm in order to use RETURN_ENUMERATOR() macro
enable ext/gdbm
implement rb_hash_delete_if()
Merge branch 'master' of git://github.com/MacRuby/MacRuby into enable_gdbm

Conflicts:
	rakelib/builder/builder.rb