Say a word if you think it's getting too much...

* added a presenter for hovercard json
* added new backbone view for handling hovercard JS
* refactoring of PeopleController

* finished the backbone js version of hovercards
* don't try to make people_controller more restfull, out of scope
  just add a new route and use that for hovercard json
* added spec for people_controller#hovercard
* add new exception for "AccountClosed" to be able to raise from anywhere

* removed legacy code, since everything got ported to backbone
  (except the "cache" stuff, but that's not strictly necessary)

Add flash warning to conversation mobile, unification of flash warning with login and register mobile, and add support for flash warning to Opera browser