Convert rfc822 module to email module
Convert rfc822 module to email module

The rfc822 module has been deprecated since python 2.3, and conversion to
the email module is straightforward, so let us do that. rfc822 is
completely gone in python3.

This also fixes a bug that led to offlineimap abortion (but that code path
is apparently usually not exercised so I did not notice:
rfc822|email.utils.parsedate return a tuple which has no named attributes,
but we were using them later in that function. So pass the tuple into a
struct_time() to get named attributes.

While reading the docs, I noticed that email.parsedate returns invalid
daylight savings information (is_dst attribute), and we are using it
anyway. Oh well, the imap server might think the mails are off by an hour
at worst.

Signed-off-by: Sebastian Spaeth <98dcb2717ddae152d5b359c6ea97e4fe34a29d4c@SSpaeth.de>
Signed-off-by: Nicolas Sebrecht <347709267ddd1958560c4c317ea3fd613f10a719@laposte.net>

frioux/offlineimap,frioux/offlineimap