SelectDescriptors/SelectDescriptors.cpp
* Fixed bug, too many parameters for stdout usage message.

VocabLib/include/VocabTree.h
* Moved weighting type definition to the VocabDB header.

VocabLib/include/VocabDB.hpp
* Defined constants for weighting, norm and distance types.
* In VocabDB class methods, using defined constants.

VocabLib/src/VocabDB.cpp
* Using defined constants in VocabDB header.
* Implemented binary weighting scheme.
* Implemented cosine distance as scoring scheme.

VocabLib/tests/VocabDB_test.cpp
* Using defined constants in VocabDB header.

VocabBuildDB/VocabBuildDB.cpp
* Using defined constants in VocabDB header.
* Added binary as weighting scheme option.

VocabMatch/VocabMatch.cpp
* Using defined constants in VocabDB header.
* Added cosine distance as scoring scheme option.

Makefile
* Separated libraries from programs compilation.