removes .idea from repo and adds it to the ignore list. reason: .idea could lead to serious conflicts for others using the same IDE and this repo.
Make the project IDE-independent by incorporating Jans idea of removing the .idea directory as well as the *.iml files.  Added *.iml to the .gitignore list.
Changed the README.md to reflect the two different ways that the project can be built (Android Studio or Cmd Line) and provides documentation on how to clone source and compile for both methods