Localizer refactoring

Localizer system needs to be refactored to help the evolution of its sub-parts such as the candidate selection. The current mechanism is as follow:

• class MFPFHLocalizer contains everything except the "objects on plane" segmentation
• class ObjectSegmentationPlane contains the "objects on plane" segmentation

The idea is to evolve for a module-based mechanism with:

• header mfpfh_types.h providing any type needed in multiple modules (e.g. the results vectors exchanged, the point types used, ...)
• class MFPFHLocalizer containing the global localization algorithm with each steps provided by a class module
• class MFPFHModel providing the structure of the model and all the functions needed to get data from it
• class CandidatesSelector providing the candidates selection methods (either the grid method used currently or any new method)
• class PoseEstimator providing the final pose estimation (using defined methods such as RANSAC+ICP or any new method)
• any other method shown usefull.

This work will be done on the refactor branch.

This work should also address the issues on \e (5) and on hard coded paths (4). Moreover, this work should prepare the system to address the packaging issues (1), (2) and (3).