HUE-1219 [impala] One page app

Removing all the mako template logic and moving to front end.
Added APIs for Beeswax.
Moved a bunch of logic from wait_results.mako and watch_query.mako
to execute.mako.
Explain uses one API now.
Make settings, file resources, and functions managed by front end.
Enable parameterization and send email notifications on front end.
Render navigator after database change via subscription to database
observable.
save and save as working with knockout.
Make typeahead source dynamically update.
parameterized queries are working with routie support.
Cancel query moved over from watch_wait.mako.
Merge remote-tracking branch 'origin/HUE-1219-abe' into HUE-1219-abe