Merge pull request #151 from jlaura/142

include/usgscsm/UsgsAstroFrameSensorModel.h

include/usgscsm/UsgsAstroPlugin.h

src/UsgsAstroFrameSensorModel.cpp

src/UsgsAstroLsSensorModel.cpp

src/UsgsAstroPlugin.cpp

tests/FrameCameraTests.cpp

tests/data/simpleFramerISD.json