Updating GSAP to 1.13.2 [author]

From https://github.com/greensock/GreenSock-JS/

- Draggable can now accommodate multiple triggers

- Fixed an issue that caused a Draggable to immediately snap inside of its bounds (when defined) the moment you clicked on it outside the bounds during a throwProps tween (imagine throwing an element outside the bounds, and before it returns, you click on it again - previously it would jump into the bounds but now it stays correctly where you click)

- Fixed warning that may appear in certain browsers like webkit about document.all not existing (it's Microsoft-specific)

- Bounds are applied immediately when a Draggable is created (instead of waiting until the user clicks/touches)

- Added suppressEvents parameter to progress() and totalProgress()

- Fixed regression that prevented CSSPlugin.defaultTransformPerspective from working properly.

- Fixed issue that could cause a seek() of a TimelineLite/Max to stop at an addPause().

- Fixed issue that could cause an invalidate() not to work as expected on a timeline (immediateRender tweens now render immediately after the invalidate())

- invalidate() now returns the virtual playhead to a time of 0.

- Fixed an issue that caused lazy rendering to ignore the suppressEvents parameter, meaning if you seek() a timeline past the point where there is an un-initted tween that has callbacks, those callbacks would get called even though suppressEvents is true for seek() by default.