Add the outgoing_bind option

Lets the admin choose a local address to bind each outgoing (IRC) socket.

Provide an adhoc option to let user pass the cert verif for some IRC servers

Fix the initial IRC nickname (was using realname, by mistake)

Implement a basic webirc support

See https://kiwiirc.com/docs/webirc

fix #3135

Fix the double sending of the USER command

Fix some trivial issues reported by cppcheck

Introduce the realname_from_jid option

When set to true, the realname and username are extracted (by default) from
the user’s JID

fix #3136

Provide the “realname_customization” option

ref #3136

The realname is also saved as an IrcClient member

Provide username and realname IRC server options

Used in the USER command when connecting to the IRC server, instead of the
first nick.

fix #3028

Connection may be closed from our side too

Add a field (in the configure form) to specifiy an after-connect IRC command

Provide Ports and TLS Ports IRC-server ad-hoc options

This let any user choose which ports to use when connecting to the IRC
server. This also lets the user choose whether or not to force TLS usage (by
setting no non-TLS port).

fix #2731

Send a PASS IRC command if the “pass” config is sot by a user, on an IRC server

fix #3068

Trivial cleanup in irc_client.cpp

Check the number of argument of every IRC command received from the server

Each IrcClient callback has a max and min size of argument, we call the
callback only if the parsed message has a correct number of arguments,
otherwise it is ignored (with a warning logged).

If hostname resolution fails, do not try all possible ports

Do not forward CTCP commands (PING, VERSION…) to the user as private messages

Some XMPP client ping themselves inside MUCs, to know if they are still in
there, this created a flood of PING message in private.  If the user is
interested in knowing when they receive a ping or version request, they can
still read their XML logs

Ignore commands that flood the user with private messages when listing chans

ref #2472

Fix the case of the nick for ping requests

fix #3041