app/views/devise/mailer/_admin.html.haml
/ If this file is changed then you must change 'devise/invitations/_admin_preview' all so.
%h4 Become an Admin
%p= "Hello #{@resource.name} <#{@resource.email}>,"
%p
#{@resource.company.owner.name} has invited you to #{link_to 'EasyKeep', root_url}, to be an admin over the
company accounts for #{@resource.company.name}. You can accept this invitation through the link below.
%p= link_to 'Accept invitation', accept_invitation_url(@resource, :invitation_token => @token)
%p
If you don't want to accept the invitation, please ignore this email.
%br/
Your account won't be created until you access the link above and set your password.