clients report their roles to the server
log role messages
add ConfigRepository
name upstart jobs "app/repo/branch"
better mock sockets in Cluster tests
server provides clients with app lists
add selector-based get() to ConfigRepository
add RepositoryTable#getRepository(basename), RepositoryTable#getRepositoryByUrl(url)

RepositoryTable now also returns (newable) Repository objects.
fix WebUi->CodebaseManager interactions
clients challenge the server to send install/upgrade bundles
fix init scripts
the server handles version messages from machines
include app name in bundle challenges
add bundle transfer logic
add Repository#createBundleStream(rev_list) and CodebaseManager#createBundleStream(app, rev_list)
remove the "git" dependency from Machine
add bundle accepting logic to Machine