bump to 2.7.0
bump to 2.7.0

industrydive/premailer,kengruven/premailer,graingert/premailer,peterbe/premailer,lavr/premailer,lavr/premailer,kengruven/premailer,peterbe/premailer,peterbe/premailer,ionelmc/premailer,graingert/premailer,ionelmc/premailer,industrydive/premailer