auto_join_bookmarks only join non-opened groupchats. Opened one are already auto-joined on re-connection. Fixes #3891

fix tooltip about logging encrypting messages. (it is now shorter, better understood (jargon removed where possible), and we it's OpenPGP and not just GPG guys {or last time I checked :$})

@bct: When moving the OTR stuff, you would've needed to adjust the
XHTML killing part. This patch fixes it. I didn't even notice since
I have XHTML disabled globally.

fixes #3963

fixes #3961

fixes #3950

fixed lock icon when session has been terminated

(Tooltips might not be complete because of some not yet addressed backend bugs)

This fixes a bug with metacontacts over different groups and should stop contact duplication in most cases.

thread id, but to even remove the lock symbol when OTR was ended
and we don't have a thread id.

Whenever we write to the underlying child_model gtk will call the _visible_func on itself.

when that event is received and the lock icon updated.

 * use correct API in session.py
 * only filter when really needed

  tag to outgoing messages anymore. Messages are not even passed to
  libotr anymore then.
* If we don't support OTR, strip OTR tags from the message before
  displaying it.