Playing around with "objc_refs" over the weekend and improved it to work on a...

Playing around with "objc_refs" over the weekend and improved it to work on a large ObjC program without running into expression timeouts. Now we get a full list of ObjC classes using a runtime function and then qsort the result. Also added code that can count all instances of each ObjC on the heap and also the total byte sizes for the object allocations.

llvm-svn: 163520