message: travis: Cache clang download
diff: @@ -21,6 +21,13 @@ addons:
  compiler: clang
  os: linux
  +cache:
  + directories:
  + build/clang+llvm-4.0.0-x86_64-linux-gnu-ubuntu-14.04/
  + build/clang+llvm-4.0.0-x86_64-linux-gnu-ubuntu-14.04.tar.xz
  + build/clang+llvm-4.0.0-x86_64-apple-darwin/
  + build/clang+llvm-4.0.0-x86_64-apple-darwin.tar.xz
  +
  matrix:
  fast_finish: true
  include:
  