as a submodule for other projects, modified the release method of py script
fixed a problem that may cause git submodule failure
move some of items to external
submodule tiny updated
對代碼結構進行了調整，隱去了部分不需要公開的函數聲明，這樣講避免與用戶創建的函數產生衝突
修正了FileManager，使用static方法替代原有的方法，這樣以後使用FileManager的方法時，便不再需要變量聲明
fixed bug
fixed some bugs and glsl shader helper modules added
more methods added in FileManager
fixed some bugs
more functions added in shader helper
bug occurs frome returning value GL_TRUE/GL_FALSE
fixed bugs
fixed bugs
patched glew32
fixed bugs, which may cause shader linking failed
fixed bugs
Merge branch 'develop'
GLM added
allow create an instance of filemanager with nothing