Command line options cleanup
Command line options cleanup

* Added 3.4 as supported Python version, it mostly works with the next
  release.

* New option group for backend compiler choice

* New option group for Windows specific stuff.

* Recommend clang 3.2 or higher

kayhayen/Nuitka,tempbottle/Nuitka,kayhayen/Nuitka,kayhayen/Nuitka,wfxiang08/Nuitka,tempbottle/Nuitka,wfxiang08/Nuitka,tempbottle/Nuitka,wfxiang08/Nuitka,tempbottle/Nuitka,kayhayen/Nuitka,wfxiang08/Nuitka