More events, delayed output, bugs fixed

- Added support for label event.
- Added support for milestoned & demilestoned actions for issue event.
- Added delayed output (10 seconds) for issue events. The script will
now fit all changes done to an issue in the same announcement.
- Added support for status events.
- Added a setting to enable (off by default) showing individual commits
to a non-default branch.
- Added number of bytes changed in an issue comment edit.
- The script will now ignore push events for creating or deleting
branches or tags since there's another event that handles those.
- More readable output for '.github list'
- Fixed the issue linker not linking to issues with really low numbers.
- Fixed issue comment event so that it doesn't always say "commented"
even if the action was edited or closed.
Strip newlines from issue comments for more meaningful output.
- Fixed problem that caused commits not to show if the committer didn't
have an account on github.
- Fixed a bug that caused multiple repositories to not work properly.
- Fixed a bug that caused events to be sent to all channels that had
that event configured.

Author: Pixelz