Replacing use of unique_ptr<T> with T* in ObjectPool.

This is done to enable building without std full supporting C++11.
PROBLEM: AutoFilterTest fails first test and hangs when exiting test.
Strengthening creation & destruction tests for ObjectPool.
Clean-up AutoFilterTest.VerifyDescendentAwareness.
Correcting leak caused by a missing delete call
Handle branching unlock conditions.

This recreates the RAII unwinding that was achieved implicitly using unique_ptr.
Merge pull request #54 from leapmotion/ref-no_unique_ptr

Ref no unique ptr