included a spectator toggle in the server admin dropdown

I have added into LobbyWidgets an action to the server admin dropdown where it acts as a toggle. 

![spectators_1](https://f.cloud.github.com/assets/2963387/2179004/cd1bb342-9687-11e3-900c-41baae5f236f.jpg)

when it is toggled (default) the game allows spectators as normal. when not toggled, all current spectators are kicked and the add spectator button dissapears.

![spectators_2](https://f.cloud.github.com/assets/2963387/2179006/ff2c13e0-9687-11e3-97ca-6d36bf27f7b5.jpg)

The exception however is the admin, who can still be a spectator at this point (if he was already when it was toggled). Figured it might be good if the admin still could.

Let me know what you guys think, its not in CnC yet as I would like your opinion on placement, logic etc.