All application specific behavior is now centralized within the app integration modules.
Plugins can now provide app integration using the --app command line option and by adding the appropriate classes to the compass module tree.
This causes your rails configuration for cache busting and asset hosts
to be picked up when generating your stylesheets. Unfortunately, all
that code runs within the context of a controller, so the stylesheets
have to be generated during first request to use this functionality.
