Merge lp://staging/~gary/launchpad/bug650343-2 into lp://staging/launchpad

Add X-Launchpad-Original-To to recipient lists; move some related files from c/l/mail to lp/services/mail.

In the reviews for https://code.edge.launchpad.net/~gary/launchpad/bug650343/+merge/37633 , I was asked to move the "incoming"-related files I touched over to lp/services/mail. This branch performs that move, and does the various changes that make lint then requests.

While we're speaking of lint, here's the output.

= Launchpad lint =

Checking for conflicts and issues in changed files.

Linting changed files:
  cronscripts/process-mail.py
  lib/canonical/launchpad/doc/emailauthentication.txt
  lib/canonical/launchpad/ftests/test_system_documentation.py
  lib/canonical/launchpad/mail/handlers.py
  lib/lp/blueprints/doc/spec-mail-exploder.txt
  lib/lp/services/mail/incoming.py
  lib/lp/services/mail/tests/incomingmail.txt
  lib/lp/services/mail/tests/test_dkim.py
  lib/lp/services/mail/tests/test_incoming.py
  lib/lp/services/mail/tests/test_signedmessage.py

./cronscripts/process-mail.py
       9: '_pythonpath' imported but unused
./lib/canonical/launchpad/doc/emailauthentication.txt
     155: want exceeds 78 characters.

The ./cronscripts/process-mail.py request is because of our weird _pythonpath dance (maybe we should make these all buildout-generated scripts someday...or not). Anyway, it's not pertinent.

The request for ./lib/canonical/launchpad/doc/emailauthentication.txt appears to not be appropriate: the test explicitly turns off whitespace normalization there, so I think the long line is intended.

Tests passed on ec2 with the current branch, except for a Windmill error that appears to be spurious.

Other than that, the only thing I know to mention is that I did not move the files I touched for this move (lib/canonical/launchpad/doc/emailauthentication.txt lib/canonical/launchpad/ftests/test_system_documentation.py lib/canonical/launchpad/mail/handlers.py). Hopefully the move request does not have to cascade like that, or I may be at this for awhile. :-)

Thank you.