add jsDelivr CDN & reformat README Installation
add jsDelivr CDN & reformat README Installation

I've set up [automated jsDelivr CDN hosting](https://github.com/jsdelivr/jsdelivr/tree/master/files/interact.js) for you.  All you need to do is make a new GitHub 'release', the PR-bot & approval should happen in minutes to hours.

I hope you don't mind the reformatting; 4 'or's are too many IMHO :)
kennygomdori/interact.js,mcanthony/interact.js,david84/interact.js,Endika/interact.js,marian-r/interact.js,naeluh/interact.js,chinxianjun/interact.js,taye/interact.js,glovebx/interact.js,bios21/interact.js,chinxianjun/interact.js,hyzhak/interact.js,taye/interact.js,adamgruber/interact.js,adamgruber/interact.js,McFarts/interact.js,hyzhak/interact.js,noahlaux/interact.js,kennygomdori/interact.js,david84/interact.js,glovebx/interact.js,bios21/interact.js,taye/interact.js,McFarts/interact.js,Endika/interact.js,naeluh/interact.js,youprofit/interact.js,elgubenis/interact.js,noahlaux/interact.js,youprofit/interact.js,mcanthony/interact.js,marian-r/interact.js,elgubenis/interact.js