[MF] add sparse matrix files to project
change half of the cold to sparse matrix
[MF] speed up dramatically with sparse matrix
[vn] fix compile error with mingw32-make
[MF] makefile profiling
Update readme.md
[MF] Profile and show call graph
[MF, VN] Update to opencv 2.4.8
[VN] update example code in main.cpp
code clean up , optimized by 8%
update setx paht.bat
Merge branch 'sparse_matrix_experiment' into develop