Write CMAKE find module

1. in order to make your own FindXXX.cmake be recognized by cmake, you 

need to add the directory holding the FindXXX.cmake to the module path as bellow 

set(CMAKE_MODULE_PATH ${CMAKE_MODULE_PATH} "${CMAKE_SOURCE_DIR}/cmake/Modules/") 

2. write the path searching script

3. set the correct variable name for your library path variable

(To be updated)