integrate the new github code review system

[thatkookooguy]

alongside the assignee mechanism

[thatkookooguy]

Almost there!

hooked to all the events and parsed the data from GitHub.

now, I just need to change the assignees to not be reviewers :-)

and do some basic tests

Currently, I'm thinking of adding the following fields:

{
  reviewers: [], // array of reviewers
  assignees: [], // array of assignees ( old reviewers )
  history: {
    reviewers: {
      removed: [] // array of removed reviewers
    }
  }
}

@Kibibit/development tell me if you guys have a different idea