Have AutoPackets keep a shared_ptr back to their parent factory.
Add facilities to AutoPacketFactory in order to gather and distribute AutoPacket lifetime statistics.
Have AutoPacket supply data to its parent AutoPacketFactory about its lifetime.
Write a simple test for the packet lifetime statistics ensuring that the count is correct, and the mean is at least not too small. Unfortunately given the uncertainty in the test environment, we cannot test the standard deviation in a unit test. For more detailed tests we must ensure we run in a high performance environment.
Needed for std::sqrt.
Merge pull request #207 from leapmotion/feature-autopacket-statistics

Feature autopacket statistics