Merge pull request #1 from abenromdhane/master

Support dynamic re-sizing for sparse matrix and training set. Add a tool for k-fold testing.
Remove serialisation functions
Remove C++ style comments
Fix build errors
Fix warnings
Remove warnings
Fix the tests suite
Fix the build
Add a binary heap structure and clean the tests

The binary heap will replace the red black matrix. Since the number of
recommended items is known in advance.
Add some comments
Fix the makefile
Fix the comments
Adapt the binary heap to support generic types
Fix the binary heap
Replace the red-black tree with a binary heap
Remove unused variables
Fix a warning
clean
Merge https://github.com/GHamrouni/Recommender

Conflicts:
	learned_factors.c
	learned_factors.h
	msvc/LibRecommender/Debug/LibRecommender.log
	msvc/LibRecommender/LibRecommender.vcxproj
	msvc/LibRecommender/LibRecommender.vcxproj.filters
	msvc/Recommender.sln
	msvc/Tests/Debug/Tests.log
	msvc/kfold/kfold.vcxproj
fix project setup