Add UMD support
Add UMD support

Add the support of AMD, CommonJS and global exports. It's needed for bundling packages and requiring with browerify (per example).

See https://github.com/umdjs/umd
miaotmac/swipe,lyfeyaj/swipe,loup-brun/swipe,EugenAz/swipe,miaotmac/swipe,loup-brun/swipe,lyfeyaj/swipe,EugenAz/swipe