Plays are working again.
Basically, after making plays for each robot become non-blocking, it was necessary to change the way a play was identified as finished. Now, the play finishes when all robots reached the last possible state.
Also, an action is considered to be finished only when the robot state is `UNDEFINED`, which occurs after the action is completed.
Removed `Play1`, which didn't have any purpose besides as an example.
The basic structure for a play has changed a little bit. `PlayFormation1`, `PlayFormation2`, `PlayStop` and `NoPlay` already implements the new structure.

Fixes #35