a replacement EmailOutputter. This is essentially the default EmailOutptter from Log4r but with the following changes:
1) if there is data to send in an email, then do not send anything 2) connect to the smtp server at the last minute, do not connect at startup and then send later on. 3) Fix the To: field so that it looks alright.
Returns the appender instance stroed in the appender hash under the key name, or nil if no appender has been created using that name.