Format phone numbers before saving conversations

Saving the national and internation versions of the number lets us use
those attributes in a typeahead collection.

js/models/conversations.js

@@ -38,6 +38,17 @@
         var required = ['type', 'timestamp'];
         var missing = _.filter(required, function(attr) { return !attributes[attr]; });
         if (missing.length) { return "Conversation must have " + missing; }
+
+        if (this.get('type') === 'private') {
+            var number = libphonenumber.util.verifyNumber(id);
+
+            this.set({
+                id: number,
+                international_number: libphonenumber.format(number, libphonenumber.PhoneNumberFormat.INTERNATIONAL),
+                national_number: libphonenumber.format(number, libphonenumber.PhoneNumberFormat.NATIONAL)
+            });
+
+        }
     },
 
     sendMessage: function(body, attachments) {