add text muted style to email layout

also added the change to the email regression tests
remove leading zero from time attribution
style the time with it's own span
increase base font-size of emails from 14px to 16px
add a small class to email.css

also updated regression tests
descrease size of time
remove unsubscribe heading
add 'small' style to subscription links
add space above subscription links with <br />
wrap subscription links in 'text-muted' div
add subscription links to place text version