fix momentjs language not applying
Start documenting backend classes
better use of momentjs for messages and extracts
Merge branch 'develop' of https://github.com/ImaginationForPeople/assembl into marionette

Conflicts:
	assembl/static/js/app/views/message.js
	assembl/static/js/require_config.js
	assembl/templates/views/message.tmpl

Spurious conflicts, the changesets were already cherry-picked and merged.