make part2, reorganize index view and js into their own files
track historical status_messages and load them upon refresh
in backend_process, rename status to state, change_status is now report_status, add publisher for state_change_event
add state_change_event setting, handle receipt of state_change_event in status_observer
selectively enable the run button based on backend_process_state
add jquery-ui and a progressbar widget
add completion_percent_event pubsub event and add UI handlers to update progressbar
clear stored status messages when state changes to running
whitespace cleanup