Fix build of Mac GTM project with static analyzer. Remove GTMGarbageCollection.  Remove GC build configs.  Remove internal dependence on GTMObjectSingleton.

DELTA=447  (49 added, 296 deleted, 102 changed)

git-svn-id: http://google-toolbox-for-mac.googlecode.com/svn/trunk@649 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3
Remove obsolete 64-bit NSNumber utility methods.

DELTA=195  (9 added, 180 deleted, 6 changed)

git-svn-id: http://google-toolbox-for-mac.googlecode.com/svn/trunk@650 7dc7ac4e-7543-0410-b95c-c1676fc8e2a3