Update to the new Play services client and added a new functionality

Added a step counter that is started if the user wants. it displays the date of start and the number of steps since that moment. It uses the total amount of steps to prevent problems in the change of days. The appearance is not the best but can be improved to match the app.

Also i added the new the new GoogleApiClient, because the GameClient now is deprecated, and the new one makes easier to add more apis like drive or g+. To change this in the project, you only have to update the BaseGameUtils from the android-samples repository in github.