cmake support for windows

Quickly added cmake support for windows

Tested on Visual Studio 2013

Instructions for Windows

1. install cmake and include in PATH variable.
2. go to build folder
3. run .cmd file corresponding to your visual studio version
    eg.  win32-msvc-2013-x86 for visual studio 2013
4. Open solution in created folder build/win32-msvc-2013-x86/cocos2dx

5. Set HelloCpp as the active project and try to run it :)
Have fun

Can I get some feedback please?
I only hacked it together quickly so I want to know does it work for others.

Martell