message: Fix instructions for building demo.
  Add --cxxopt='--std=c++11' to instructions.
diff: @@ -180,7 +180,7 @@ After editing your WORKSPACE file to update the SDK/NDK configuration, you may
  build the APK. Run this from your workspace root:
  ```bash
  -bazel build -c opt //tensorflow/examples/android:tensorflow_demo
  +bazel build --cxxopt='--std=c++11' -c opt //tensorflow/examples/android:tensorflow_demo
  ```
  ##### Install
  