Command-line automation for Android E2E Test App

Added command-line based automation for the Android E2E Test App. This includes:
- Batch file which can be used to start the automation, and detect when the tests are done
- Changes to the test app itself:
  - take parameters from a file (on external storage) passed by the batch file
  - start running tests immediately based on the file
  - Automatically post logs / results to the HTTP server
  - writes a file (on external storage) to notify the script that the tests are done

It currently only supports tests which can be run without user intervention (i.e., login tests are excluded).