[#53420683] Adds a page detailing the process of setting up group registration.

Requires https://github.com/AllPlayers/brochure.allplayers.com/pull/154.


![1](https://f.cloud.github.com/assets/2251119/1624650/f4a011b2-56c5-11e3-96f0-afd00c15b7b5.png)


![2](https://f.cloud.github.com/assets/2251119/1624651/f4b211d2-56c5-11e3-856f-4caaea7312a3.png)


![3](https://f.cloud.github.com/assets/2251119/1624652/f4bec4c2-56c5-11e3-8dbb-e88094fa3f4c.png)


![4](https://f.cloud.github.com/assets/2251119/1624653/f4c3c878-56c5-11e3-80d3-cbe0e6a3fafc.png)


![5](https://f.cloud.github.com/assets/2251119/1624654/f4c3e952-56c5-11e3-8eba-461d8318198c.png)


![6](https://f.cloud.github.com/assets/2251119/1624655/f4c5c542-56c5-11e3-8831-4fb837fcd147.png)