added BaseTools/Makefile

added      BaseTools/Makefile
modified   BaseTools/Source/Python/Makefile
modified   BaseTools/toolsetup.bat
  Moved code from toolsetup.bat into Makefile and Source/Python/Makefile
  in order to separate out C and Python building.  Now after the
  environment is initialized, you can just run nmake to build both C and
  Python tools.  Alternatively you can run 'nmake c' or 'nmake python'
  to only build the applicable set of tools.

git-svn-id: https://buildtools.tianocore.org/svn/buildtools/trunk/BaseTools@902 7335b38e-4728-0410-8992-fb3ffe349368