Update CONTRIBUTING.md
add license info
Update README.md
bug fixes and add functions
add namespace clustering
initial version of cmake

This still has some bugs, just for backup.
fixes bug: ml install
[cmake] add lib ver num and debug mode notation
[bug fixes] make nadd2013 is workable
bug fixes
Merge pull request #3 from yunfuliu/CMake

Add functionality of supporting CMake
add manual
Rename MANUAL.txt to MANUAL.md
Update MANUAL.md
Update README.md
Merge branch 'master' of https://github.com/yunfuliu/pixkit
add two enhancement functions
remove std namespace
Merge pull request #2 from JieCyun/master

bug fixes and add two enhancement functions
add two corresponding examples