Issue #10: Made Calibrator class able to calibrate from pictures
Description:
Since now you can calibrate camera from pictures. Having an object of Calibrator class just call reinitCaptureFieldWithImagesPath method with path to images taken by device as an argument and then call execute().

For example:
calibrator.reinitCaptureFieldWithImagesPath("images/left/image%02d.jpg");
calibrator.execute();

will make calibration based on image00.jpg, image01.jpg, image02.jpg, ... files in images/left/ direcetory.