On GitHub, issue links are automatically created: if a user types, "#123", it will link to issue #123. Bugzilla has the same feature: "Bug 123" will link to Bugzilla bug 123.
This feature adds Bugzilla linking support to GitHub: in comments, it links text of the form "Bug 123" to their associated Bugzilla bugs.
This feature works together with the Hoist Bugzilla Bugs feature so that these bugs and their statuses are hoisted to the top of the issue.