A LineMOD trainer node for ROS

This nominally runs using OpenNI data. It's going to get changed and
broken into training and detection nodes probably
Removed unused classes and callback
Detection only node. Still needs outputs
Created NamedPoint message
Made the template file a param
Added disparity callback, removed unnecessary filename declaration
Actually build NamedPoint message
Added publishing of image space NamedPoint with similarity threshold
Added depth extraction from disparity image
Added library that defines new InnerColorGradient modality

This still needs to be tested, but it all builds and appears to import
correctly in the trainer
Detector listens to CameraInfo for projection matrix
Fixed topic naming dumbness