* Added itkSimilarityTransform including "stage" parameters "rotation_scale" and "scaling_scale" in addition to already existing "translation_scale" parameter. In accordance with "Translation_Scale" parameter rotation- and scaling_scale are defined using "rotation_scale = 1.0 / (double) stage->rotation_scale_factor;" and "const double scaling_scale = 1.0/ (double) stage->scaling_scale_factor;". "rotation_scale" can now also be used as parameter for rigid and affine transform (default values are unchanged, test for rigid an affine transform passed wihtout update)
* Added 6 tests to test similarity transform: plm-reg-itk-similarity, plm-reg-itk-similarity-stats-1, plm-reg-itk-similarity-check-1, plm-reg-itk-similarity-stats-2, plm-reg-itk-similarity-check-2, plm-reg-itk-similarity-check-2 + one new "test" to create a new synthetic dataset (rect-2s) + registration config file (Testing/data/plm-reg-itk-similarity.txt)