Event admins send messages to sessions (no tests yet)
Add tests for event->session messages
Fix error hiding modal
Decrease timeout for re-posting messages to 5000.
Style and cleanup fixes post-merge

 - Replace -webkit- specific style with cross-browser
 - Move .brand styles to stylesheet (scoped as `.navbar-inverse .brand`
   to successfully override bootstrap default)
 - Rewrite .participant-info markup and styles, hopefully will fix
   issue #163
 - Kept with 4-spaces for js, 2-spaces for HTML/styl, expressing my
   inner pedant.
 - fixed font-awesome CDN link
 - moved modals to footer, for better screen-reader friendliness
 - moved modal-footer out of modal-body.
Merge branch 'message-sessions' into header-ui