networkAgent: add support for EAP-FAST password requests

EAP-FAST is a top-level EAP method like TTLS, PEAP, etc.

https://bugzilla.gnome.org/show_bug.cgi?id=719813

js/ui/components/networkAgent.js

@@ -255,6 +255,7 @@ const NetworkSecretDialog = new Lang.Class({
         case 'leap':
         case 'ttls':
         case 'peap':
+        case 'fast':
             // TTLS and PEAP are actually much more complicated, but this complication
             // is not visible here since we only care about phase2 authentication
             // (and don't even care of which one)