KMajorityLib/include/CentersChooser.h
VocabLib/tests/VocabTree_test.cpp
* Seeding random number generator was moved to the specializing class.

VocabLib/include/VocabTree.h
* Changed default tree depth since it uses a 0 based index and to obtain
1 million descriptors it needs depth 7.
* Re-implemented methods to save/load tree and use a flat structure
instead of a nested one.
* Using params object to initialize VocabTree attributes.