Add 6to5 to README
Add 6to5 to README

atom/electron-starter,dkfiresky/electron-starter,kittens/atom-shell-starter,atom/electron-starter,xmail-client/xmail,kittens/atom-shell-starter,amine7536/electron-starter,atom-archive/electron-starter,amine7536/electron-starter,dkfiresky/electron-starter,atom-archive/electron-starter,sebmck/atom-shell-starter,liuxiong332/xmail,liuxiong332/xmail,dkfiresky/electron-starter,sebmck/atom-shell-starter,atom/electron-starter,xmail-client/xmail,xmail-client/xmail,xmail-client/xmail,amine7536/electron-starter,xmail-client/xmail,sebmck/atom-shell-starter,git-notes/git-notes,liuxiong332/xmail,git-notes/git-notes,atom-archive/electron-starter,liuxiong332/xmail,liuxiong332/xmail,sebmck/atom-shell-starter,git-notes/git-notes,kittens/atom-shell-starter,kittens/atom-shell-starter