Issue #9: Added methods to save calibration results
Additional changes:
-added StereoCalibrationData class which inherit from CalibrationData
-introduced StereoCalibrationData into StereoCalibrator class
Merge branch 'master' of https://github.com/przem14/Computer-Vision

Conflicts:
	src/StereoCalibrator.cpp
	src/StereoCalibrator.h