Add discovery tool for Wintermute.

  * Add 'FindWintermute.cmake' generation.
Updated core modules for Wintermute in CMake.

  - WintermuteDependencies.cmake
    * Git is now a dependency for building Wintermute.

  - WintermuteMacros.cmake
    * Corrected issue with defining compile flags dependent on build-type.

  - WintermuteVariables.cmake
    * Changed the C++ type from 'C++11' to 'C++0x'.