WIP:add application to compute features from image

The code was first developed in the context of the CNES R&T study Venise by Julien Michel. The translation in a OTB application and some modifications were done by Jens Ziehn during his intership at CNES in 2011.
The aim of this application is to provide similar functionnality as the FeatureExtraction module in Monteverdi. For now it contains (hog, fourrier-mellin,histogram,haralick textures) and flusser moments.
There are some improvments to add to the application (documentation, compute features separately...)