message: Added clear function to renderer.
diff: @@ -270,6 +270,12 @@ export default class WebGLRenderer extends SystemRenderer
  return this;
  }
  + clear()
  + {
  + this.framebuffer.bind();
  + this.framebuffer.clear();
  + }
  +
  /**
  * Removes everything from the renderer (event listeners, spritebatch, etc...)
  *
  