Allow major upgrades

gui/scripts/syncthing/core/controllers/syncthingController.js

@@ -698,6 +698,7 @@ angular.module('syncthing.core')
 
         $scope.upgrade = function () {
             restarting = true;
+            $('#majorUpgrade').modal('hide');
             $('#upgrading').modal();
             $http.post(urlbase + '/system/upgrade').success(function () {
                 $('#restarting').modal();
@@ -707,6 +708,10 @@ angular.module('syncthing.core')
             });
         };
 
+        $scope.upgradeMajor = function () {
+            $('#majorUpgrade').modal();
+        };
+
         $scope.shutdown = function () {
             restarting = true;
             $http.post(urlbase + '/system/shutdown').success(function () {