Helper tool

Here is a first crack at a helper tool based on the pen I showed you and the grid you already have in the demo. 

## Features
* Provides jquery-focuspoint data attributes & CSS background-position in inputs for easy copy/paste.
* Input for pasting in your own image path to use in the demo - will update aforementioned fields accordingly.
* Added GreenSock GSAP for animation
* * Animated transition when you click on a new focuspoint
* * Animated Target Reticle
* Added new Image from unsplash.com (just so we have on in there without a reticle already on it).

### Issues
* GSAP tweens get a little clunky - I think it probably has to do with calling .adjustFocus() so many times consecutively. Perhaps we should make a special method in focuspoint optimized for animation?
 
Let me know what you think!