Add note about skipping header
Add note about skipping header

Closes #113

controlshift/premailer-rails,controlshift/premailer-rails,uswitch/premailer-rails,fphilipe/premailer-rails,doorkeeper/premailer-rails,fphilipe/premailer-rails,controlshift/premailer-rails,fphilipe/premailer-rails,doorkeeper/premailer-rails,uswitch/premailer-rails