fix compilation OpenCV with cxx11 under Ubuntu with clang and gcc 4.7

The labels of a model are now cloned instead of using Mat::copyTo, because Mat::copyTo leads to a crash with the Python wrapper. I need to further investigate it.

added openfabmap code, contributed by Arren Glover. fixed several warnings in the new versions of retina filters

updated Retina module code for more flexible parallelisation : TBB parallel for loops are replaced by opencv parallel_for_ wrapper... compile error corrected

updated code for more flexible parallelisation : TBB parallel for loops are replaced by opencv parallel_for_ wrapper

Retina module is now parallelized thanks to the TBB library. Speed increase expected on multicore plateforms

Issue #2231: Attempt to fix segfault, when copying labels. LDA needed to be updated to generate the Wrapper correctly.

facerec.cpp: Removed Original LBP wrapper, because it is not in use and therefore generates a warning.

facerec.cpp: Added an exception to the LBP extraction, so now a meaningful exception is thrown if the wrong image type was given. Thanks to Eric Christiansen for reporting.

FaceRecognizer supports updating a model now. Documentation has been updated to reflect latest changes.

Updated the train method to be an InputArrayOfArrays, so the Python wrapper now generates the correct code (and it works).

Fixed facerec_eigenfaces.cpp demo sample: it contained hardcoded values, which made wrong element access possible. Fixed unsigned integer/signed integer warnings in facerec.cpp.

Bug #2214: Fixed bug, when calling the train method multiple times. The Eigenfaces and Fisherfaces method now re-estimate the model, the LBPH method appends the new data to the existing model.

Changed DetectionBasedTracker a bit to make its method addObject to return an integer value -- the id of the new added object.

Added possibility in the class DetectionBasedTracker to work as a tracker only -- without the mainDetector. 
In this case new objects will be added into it by the method addObject(const cv::Rect& location).

revision 8721 vas merged to head. Detection based tracker interface changed. cpp and android samples updated.

Warning: changes beak binary compatibility