Work on the user account system

Allow a user to modifies its name, username, initials, and password.

Fixes username handling on sandstorm.

Fixes #149.

client/lib/popup.js

@@ -202,9 +202,9 @@ $(document).on('click', function(evt) {
   }
 });
 
-// Press escape to close the popup.
+// Press escape to go back, or close the popup.
 var bindPopup = function(f) { return _.bind(f, Popup); };
 EscapeActions.register('popup',
-  bindPopup(Popup.close),
+  bindPopup(Popup.back),
   bindPopup(Popup.isOpen)
 );