[travis] employ workaround to use newer llvm version: https://github.com/travis-ci/travis-ci/issues/6120#issuecomment-224072540
[travis] employ workaround to use newer llvm version: https://github.com/travis-ci/travis-ci/issues/6120#issuecomment-224072540

readdy/readdy,readdy/readdy,readdy/readdy,readdy/readdy