Remove UMD from src/interact.js
Remove UMD from src/interact.js

browserify's standalone option can produce UMD

adamgruber/interact.js,marian-r/interact.js,taye/interact.js,Endika/interact.js,adamgruber/interact.js,taye/interact.js,taye/interact.js,bios21/interact.js,bios21/interact.js,marian-r/interact.js,Endika/interact.js