docs(forms.ngdoc): fix spacing in example

Closes angular#3930

Author: anthonypt87

docs/content/guide/forms.ngdoc

@@ -154,10 +154,10 @@ This allows us to extend the above example with these features:
 
 <script>
   function Controller($scope) {
-    $scope.master= {};
+    $scope.master = {};
 
     $scope.update = function(user) {
-      $scope.master= angular.copy(user);
+      $scope.master = angular.copy(user);
     };
 
     $scope.reset = function() {