Applications
This repository contains all files that form the applications subtree for the master repositories (e.g. core, mask, kick, chat, skin, bits, reap). It focuses on providing logic for the different applications each master server runs. (e.g. core server could run app).
By separating the application logic into this self-contained subtree, all changes to this code base can be centrally administrered. Master repositories get updated by pulling their subtrees from Github.
See also http://blogs.atlassian.com/2013/05/alternatives-to-git-submodule-git-subtree/