OpenNI2 driver modification.
Merge branch 'OpenNI2_mod' of https://github.com/KMiyawaki/mrpt into OpenNI2_mod

Conflicts:
	libs/hwdrivers/include/mrpt/hwdrivers/COpenNI2Generic.h
	libs/hwdrivers/src/COpenNI2Generic.cpp
	libs/hwdrivers/src/COpenNI2Sensor.cpp
	samples/openNI2_to_rawlog/test.cpp