Include a private and no-copy nodes in private <message/> to avoid carbon duplication

Parse the timezone myself, instead of using the broken strptime

See

https://lab.louiz.org/louiz/biboumi/issues/3215
https://github.com/andikleen/glibc/blob/master/time/strptime_l.c#L746-L747

for why strptime() sucks

We use std::get_time now, to parse the date and time. And we parse the
timezone by hand.

fix #3215

Fix the muc#traffic response

Was completely broken, and the test was just useless

Correctly set status="110" in the presence for the target of a kick

e2e: add expec_unordered to be able to test things even if the arrive in a different order

Also, some tests that were raising some exception and thus were not ran at all

fix #3213

Cleanup __main__.py a little bit

Add a coverity badge to the readme

Remove a potential nullptr dereference, on mam queryid

fix coverity CID 153376

Add a coverity job that runs cov-build and submit the archive to coverity.com

Fix the argument of strerror after bind()

fix coverity CID 134470

Remove a branch that execute identical code in both cases

fix coverity CID 134469

Avoid sending PART command for unjoined channels

fix #3205

Update the changelog

Respond to muc#traffic requests

fix #3069

Make version requests work with global user JIDs as well

fix #3210

Avoid an exception due to some bad logic in the DNS resolution mechanic

fix #3207

Fix some compilation warning/errors that appear on FreeBSD

Fix parse_datetime by always using a 'z' as the timezone

Because some plateform accept Z and z, but some only accept z…

Remove build/* from the coverage, because that code isn’t part of biboumi

Add missing include file