Document bot/server setup, commands in GitHub Wiki

[skyegallup]

BrickHack and other hackathon servers will likely be setup by people without intimate knowledge of this bot's inner workings. Proper documentation is needed to explain how to correctly setup these servers so that the bot may function effectively.

We should also take time to add internal (read: in the code) documentation, especially for things like the per-command methods.

[skyegallup]

Needs to be fast-tracked for two reasons:
1.) Chris needs to setup a staging server for bot testing, which requires a setup guide.
2.) We might be working on BH guild setup soon w/ Mark, which would be easier with documentation

[skyegallup]

#17 (fix build commands) and #14 (mentor-only commands) need to be merged before this can be merged.

[skyegallup]

External documentation done in issue-4 and wiki. Still need to work on internal documentation a bit more, however.