Updated the EDIT/ADD shortcuts on Map

* Updated Leaflet version (Draw required version 0.6+)
* Updated Wax version (just to kep it in sync)
* Added Leaflet.Draw to easily add Marker (and later polygons)
* Added Mapbox.js as custom layers were not working anymore on new leaflet.
* Modal is now removed if screen size is too small
* Geocode of marker are sent to Add Submission URL (but Enketo doesn't understand it yet)
* Added a refresh button so user can reload if he added/changed data.