don't parse mail signatures of mails sent with commands

[Christian Boltz]

Launchpad has the nice feature that you can comment on a bug by sending a mail to $<email address hidden>

This is a good feature, but it needs some finetuning ;-)

I sent a mail that ended up on https://bugs.launchpad.net/ubuntu/+source/cups/+bug/908864 as comment #7. The result was a mail from launchpad saying

** Bug watch added: Novell/SUSE Bugzilla #159223]
   https://bugzilla.novell.com/show_bug.cgi?id=159223]

I was surprised because I didn't mention any novell bug in my mail, and then I noticed that my random signature for this mail was

--
> Status?
NEW
[Ihno Krumreich and Stephan Kulow on
https://bugzilla.novell.com/show_bug.cgi?id=159223]

Please stop parsing a mail when you hit a signature delimiter (newline minus minus space newline) to avoid such false positives and/or don't include the signature in the bug comment.