Re: #435 - Collection Days: leaflet map, mobile implementation

* upgraded chosen to 1.2.0
Re: #435 - Collection Days: leaflet map, mobile implementation

re-factored for new implementation concept

* markers are spearated into past and upcoming
* in mobile context, only upcoming markers are displayed
* in mobile context, past contribution dropdown is hidden
Re: #435 - Collection Days: leaflet map, mobile implementation

* adjusted map height for mobile and larger devices
Re: #435 - Collection Days: leaflet map, mobile implementation

* re-factored so that we can add an onclick event to map markers
* implemented the use of the map marker onclick event in a mobile context
localeapp update
Re: #435 - Collection Days: leaflet map, mobile implementation

in mobile context:

*  no map when there are no upcoming events
*  display a no events message when there are no upcoming events
*  deeper zoom when only one upcoming event
Re: #435 - Collection Days: leaflet map, mobile implementation

* updated leaflet.js
Re: #435 - Collection Days: leaflet map, mobile implementation

* added animated feedback to marker clicks which redirect the user to the collection day pages
Re #371: Do not sweep contact cached fragments unless associated with a user.
Re: #426 - Collection Days: Previous, without content

* added logic to remove map zoom control when no stories are present
Re #454: Prevent mass-assignment of cataloguer when updating contribution.
Re #490: Allow non-cataloguer user to be contribution cataloguer if already saved.