Add Main Application of RAD Teams

From [Document applying RAD Feature](https://trello.com/card/document-applying-rad-for-play-by-example/4fdf69290bbdfd35030ca73b/2)

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The results of this should be a simple and clear description of: 

- how to do RAD (rapid async, development) in Play by Example
- the work flow requirements, ie: using the trello board, etc.
- a real test if RAD principles actually work :)