[CMake] add_llvm_library: Add "RUNTIME DESTINATION bin" to install(). It affects add_library(SHARED) for Win32.DLL.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212818 91177308-0d34-0410-b5e6-96231b3b80d8
llvm/test/lit.cfg: Let %python available.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@212819 91177308-0d34-0410-b5e6-96231b3b80d8