[lit] Add --version option.

git-svn-id: http://llvm.org/svn/llvm-project/llvm/trunk/utils/lit@203496 91177308-0d34-0410-b5e6-96231b3b80d8
[lit] Add a README.txt.
 - Also, update MANIFEST.in and utils/check-sdist.

git-svn-id: http://llvm.org/svn/llvm-project/llvm/trunk/utils/lit@203497 91177308-0d34-0410-b5e6-96231b3b80d8
[lit] Bump dev version number.

git-svn-id: http://llvm.org/svn/llvm-project/llvm/trunk/utils/lit@203498 91177308-0d34-0410-b5e6-96231b3b80d8