add minimal functions of EigenFaces
Merge branch 'develop' into feature/add_FaceRecognizer

Conflicts:
	Manifest.txt
	ruby-opencv.gemspec
add EigenFaces#save
add EigenFaces#load
add a test case of EigenFaces#save
Merge branch 'develop' into feature/add_FaceRecognizer
add FaceRecognizer class and modify EigenFaces to inherit it
fix comment
update Manifest.txt and ruby-opencv.gemspec
add Algorithm class and modify FaceRecognizer to inherit it
Merge branch 'develop' into feature/add_FaceRecognizer
update Manifest.txt and gemspec
Merge branch 'develop' into feature/add_FaceRecognizer
Merge branch 'develop' of github.com:ruby-opencv/ruby-opencv into develop
Merge branch 'develop' into feature/add_FaceRecognizer

Conflicts:
	ruby-opencv.gemspec
add CvMat#apply_color_map
add some constants of CvMat depth
modify CvMat#normalize to use depth type parameter
fix CvMat#apply_color_map for invalid parameter
add CvMat#subspace_project and CvMat#subspace_reconstruct