Improve Emails (used to be 317 checkin emails)

Per issue 317, when a user returns a piece of overdue equipment, UserMailer sends an email to the user with the name of the equipment, its notes, and the late fee. AdminMailer sends a very similar email to the admin with the same information.
These all look like tab / spacing changes. If the files aren't related to the actual change should we leave the diffs out of this pull request and maybe just script an app-wide update of the spacing, or should we just update spacing piecemeal as we go along?