Added Fine Grained Saliency algorithm

Since now there is a saliency module, I would like to add an implementation of fine grained saliency, which fits nicely in the static section of the module.

Fine grained saliency is based on algorithms described in:
Montabone, Sebastian and Soto, Alvaro. "Human Detection Using a Mobile Platform and Novel Features Derived from a Visual Saliency Mechanism." Image and Vision Computing, 2010.

This pull request implements the staticSaliencyFineGrained class, so that a new saliency algorithm FINE_GRAINED is available. The code was originally released at http://www.samontab.com/web/saliency

You can see an example of it here:
![saliency_of_stuff](https://cloud.githubusercontent.com/assets/1005152/4945015/394c98ba-6603-11e4-864c-ffd50f0d73eb.jpg)


sorry, we disallow the use of IplImage in the newly added code; please, use C++ Mat instead.