Fixed the HashMap detection in CMake.
Fixed the HashMap detection in CMake.

The main problem was that cached variables were not unset in the foreach
loops. So only the first entry in each list was looked at (namespaces,
etc. Now only the HashMap implementation needs to be fixed for the
other non tr1 hash_maps/unordered_sets.

tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball,tkemmer/ball