display real error message when carddav sync fails
hide mark as read button if no unread message #LINQT-2144
fix screencast panel hidden while user is sharing screen #LINQT-2136
disable selection for cancelled meetings #LINQT-2121
try to remove ffmpeg dependency #LINQT-2015
Clean friends manager maps when restarting app as the linphone core will be reset (fix #LINQT-1933)
only show error message once when linphone restarts if remote configuration failed #LINQT-2030
auto update contact list on carddav synchronized (fix #LINQT-1983)
