Leap.mx

o Use CouchDocument to comply with new Soledad couch backend. Fixes
4475.
o Some emails are multipart and each part has its own encoding.

o Add X-Leap-Provenance header. Closes 4356.
o Add tester script to ease testing problematic emails offline.

o Some mail may be skipped at processing because of possible
problems (like connectivity issues to our couch nodes), MX now
looks for unprocessed mails every half hour and tries to process
them. Fixes 3628.

o Fix return codes for check recipient access. Fixes 3356.
o Improve logging in general and support possible unicode parameters
without breaking.
o Try to figure out the encoding of an email first by looking into
its header, if that fails then by using chardet.
o Support more than utf8 encodings for emails.
o Add support for receiving mailing list mails.
o Use the uuid that alias_resolver returned and postfix added to the
mail headers, which improves performance.
o Look for public keys based on uuid instead of mail address.

o Keep file watcher in memory to prevent losing file events.
o Properly save the incoming mail as a doc in couch.
o Properly parse mail address of the form "Name <userdomain>". Fixes 3653.

o Migrate mx functions to work on the new couchdb structure and
views. Fixes 3502.
o Update to new soledad package scheme (common, client and
server). Closes 3487.
o Add versioneer.