message: Fix broken link in tfmobile documentation
  This fix fixes the broken link in tfmobile documentation as
  android/ had been moved to android/tfmobile/ in the repo
  googlecodelabs/tensorflow-for-poets-2
diff: @@ -27,7 +27,7 @@ called `libandroid_tensorflow_inference_java.jar`. There are three ways to
  include this functionality in your program:
  1. Include the jcenter AAR which contains it, as in this
  - [example app](https://github.com/googlecodelabs/tensorflow-for-poets-2/blob/master/android/build.gradle#L59-L65)
  + [example app](https://github.com/googlecodelabs/tensorflow-for-poets-2/blob/master/android/tfmobile/build.gradle#L59-L65)
  2. Download the nightly precompiled version from
  [ci.tensorflow.org](http://ci.tensorflow.org/view/Nightly/job/nightly-android/lastSuccessfulBuild/artifact/out/).
  