drop default MTA for Fedora 15

[Michael Cronenworth]

Matthew Garrett wrote:
> The long term fix would arguably be to provide a stub /usr/sbin/sendmail
> that ties into a more generic event reporting interface, which in turn
> could be configured to send mail elsewhere but would default to popping
> up some sort of desktop notification.

Already works that way. Sendmail/logwatch deliver e-mail and DeviceKit 
displays desktop notifications (without requiring an MTA).