Update to libpurple-2.4.2.

o In MySpaceIM, messages from spambots are discarded (Justin Williams)
o Strip mIRC formatting codes from quit and part messages.
o IRC now displays ban lists in-channel for joined channels.
o Fixed a bug where the list of loaded plugins would get removed when
  switching between different operating systems.
o Fix reception of IRC PART without a part message on Undernet
  (fixes a problem with litter in the channel user list).
o IRC no longer crashes on /list on servers which erroneously omit RPL_LISTSTART
o Update the NetworkManager support to use D-Bus directly, instead of
  libnm-glib. Hopefully it's stable now. It will now compile by default if you
  have D-Bus support and NetworkManager.h. (Elliott Sales de Andrade)
o MSN buddy list synchronization is now more forgiving, only asking about
  buddies who have disappeared completely from the server list and not those
  that have simply moved groups.
o IRC will now try to append 1-9 to your nick if it is in use, instead of
  substituting the last character with 1-9 where possible.
o Bonjour buddies will be saved persistently if they're moved out of the
  "Bonjour" group. (Eion Robb)

(tnn)