prepare server for description + misc i18n fix
add long description field & handle errors
handle errors in popover
modal on 2 columns when screen is big enough, some style tweaks
brunched
move rrule to modal right-column
Merge branch 'master' of https://github.com/aenario/cozy-agenda

Conflicts:
	client/app/views/calendar_popover.coffee
	client/public/javascripts/app.js
	client/public/javascripts/vendor.js
	client/public/stylesheets/app.css
Merge branch 'master' of https://github.com/aenario/cozy-agenda

Conflicts:
	client/app/views/templates/event_modal.jade
	client/public/javascripts/app.js