$animate.enabled() is also callable w/o params (DefinitelyTyped#9961)

* $animate.enabled() is also callable w/o params

* Removed one overload in favour for optional parameter.

Author: Andrew Mayorov

angularjs/angular-animate.d.ts

@@ -69,8 +69,8 @@ declare namespace angular.animate {
         * @param value If provided then set the animation on or off.
         * @returns current animation state
         */
+        enabled(value?: boolean): boolean;
         enabled(element: JQuery, value?: boolean): boolean;
-        enabled(value: boolean): boolean;
 
         /**
          * Cancels the provided animation.