Continue to check message for HL words after we found one that could be only the beginning of another real word.

roster : Fix resource problem, gajim.contacts.get_contact() can return first contact instead of specified resource. Fixes #3789.

Single window mode to any other resulted in the roster being the size of the roster + any chats that were in the orignal window.  This fixes that. (#3713)

show invitation from anonymous room in roster from a groupchat rather than from a normal Contact. fixes #3448

-Check if there are pending events and send offline even if we don't ask a status message (was a indentation
mistake I think)
- Really make unread and recent working according to 'notify_on_all_muc_messages' value
- be faster, hopefully

Use only one function when user wants to quit. Bad dup code !
Maybe see #3643.

faster
- Stop adding pm chat messages received to unread messages. This is in addition to [8311], but
works also when chat win is already opened now.
- Automatically remove unread_message lines for messages older than a month, so we will clear this
table for everybody, and keep it quite clear. Specially because messages can still be blocked here
if it's from someone not in the roster and we don't open it during the session. This can be long
at first connection with this version, because we delete a lot of lines (nearly one per PMs you
received since a long time). Could also be a very little longer during one month.

Stop loading all transport iconsets at launch. Load them on the fly, if and when needed. Speedup gajim start and
use less mem :)