Transition to revision numbers for groups instead of timestamps
Add snapshot support to lib/dispatch.js
Style tweaks
Pass a snapshot along when generating HTML pages
Dispatcher should be an EventEmitter
Rename the "invalidate" event to "refresh"
Remove the Dispatcher.change method, it belongs in the frong-end client
Propagate URL refreshes to the front-end
Add the revision number to all "refresh" messages
Implement a basic client-side script