Add 'loose' option link for babel-preset-env (#7241)
Add 'loose' option link for babel-preset-env (#7241)

- Added a external link to a good explanation of “loose” transformations.
http://2ality.com/2015/12/babel6-loose-mode.html
hulkish/babel,kaicataldo/babel,kellyselden/babel,samwgoldman/babel,hzoo/babel,kaicataldo/babel,kellyselden/babel,existentialism/babel,maurobringolf/babel,maurobringolf/babel,babel/babel,existentialism/babel,hulkish/babel,Skillupco/babel,hzoo/babel,chicoxyzzy/babel,guybedford/babel,babel/babel,jridgewell/babel,hulkish/babel,kellyselden/babel,kellyselden/babel,kaicataldo/babel,jridgewell/babel,Skillupco/babel,Skillupco/babel,existentialism/babel,Skillupco/babel,chicoxyzzy/babel,vadzim/babel,hulkish/babel,jridgewell/babel,PolymerLabs/babel,kaicataldo/babel,guybedford/babel,chicoxyzzy/babel,PolymerLabs/babel,hzoo/babel,PolymerLabs/babel,chicoxyzzy/babel,vadzim/babel,jridgewell/babel,babel/babel,hzoo/babel,samwgoldman/babel,maurobringolf/babel,samwgoldman/babel,babel/babel,guybedford/babel