gui: Improve display of local size, ignore pattern status (fixes #3623)

The discrepancy between global and local sizes is fine and expected in
the presence of ignores. This just moves the "we have ignore patterns"
indication to the actual local size metric, as an explanation of why it
may differ from the global size...

gui/default/syncthing/core/syncthingController.js

@@ -690,6 +690,15 @@ angular.module('syncthing.core')
             return 'info';
         };
 
+        $scope.neededItems = function (folderID) {
+            if (!$scope.model[folderID]) {
+                return 0
+            }
+
+            return $scope.model[folderID].needFiles + $scope.model[folderID].needDirectories +
+                $scope.model[folderID].needSymlinks + $scope.model[folderID].needDeletes;
+        };
+
         $scope.syncPercentage = function (folder) {
             if (typeof $scope.model[folder] === 'undefined') {
                 return 100;