Leap.mail

o Uses deferToThread for sendMail. Closes 3937
o Update pkey to allow multiple accounts. Solves: 4394
o Change SMTP service name from "relay" to "gateway". Closes 4416.
o Identify ourselves with a fqdn, always. Closes: 4441
o Remove 'multipart/encrypted' header after decrypting incoming
mail. Closes 4454.
o Fix several bugs with imap mailbox getUIDNext and notifiers that
were breaking the mail indexing after message deletion. This
solves also the perceived mismatch between the number of unread
mails reported by bitmask_client and the number reported by
MUAs. Closes: 4461
o Check username in authentications. Closes: 4299
o Reject senders that aren't the user that is currently logged
in. Fixes 3952.
o Prevent already encrypted outgoing messages from being encrypted
again. Closes 4324.
o Correctly handle email headers when gatewaying messages. Also add
OpenPGP header. Closes 4322 and 4447.

o Add support for non-ascii characters in emails. Closes 4000.
o Default to UTF-8 when there is no charset parsed from the mail
contents.
o Refactor get_email_charset to leap.common.
o Return the necessary references (factory, port) from IMAP4 launch
in order to be able to properly stop it. Related to 4199.
o Notify MUA of new mail, using IDLE as advertised. Closes: 3671
o Use TLS wrapper mode instead of STARTTLS. Closes 3637.

o Do not log mail doc contents.
o Comply with RFC 3156. Closes 4029.

o Improve charset handling when exposing mails to the mail
client. Related to 3660.
o Return Twisted's smtp Port object to be able to stop listening to
it whenever we want. Related to 3873.

o Remove cleartext mail from logs. Closes: 3877.

o Make mail services bind to 127.0.0.1. Closes: 3627.
o Signal unread message to UI when message is saved locally. Closes:
3654.
o Signal unread to UI when flag in message change. Closes: 3662.
o Use dirspec instead of plain xdg. Closes 3574.
o SMTP service invocation returns factory instance.