Create mFASTConfig.cmake and mFASTConfigVersion.cmake

Create mFASTConfig.cmake and mFASTConfigVersion.cmake
files to be used in find_package() by projects that
depend on mFAST

After applying this commit, users could use mFAST in their cmake projects very easily:
e.g.
```cmake
# mfast_static used by default, suffix _static should be ommited for shared libs
find_package(mFAST REQUIRED COMPONENTS decoder_static json_static)  
```
Currently components just affect linker command line (e.g. you should not link against mfast_json_static if you don't use it). 

Description and example of similar setup:
http://www.cmake.org/Wiki/CMake/Tutorials/How_to_create_a_ProjectConfig.cmake_file