Move libcxx/test/libcxx python package into libcxx/utils/libcxx.

This patch merges the test python package with the newly
created package in utils.

git-svn-id: https://llvm.org/svn/llvm-project/libcxx/trunk@294651 91177308-0d34-0410-b5e6-96231b3b80d8
13 files changed