Instead it is part of Manager which is already itself a singleton
When the client requests termination of the daemon, the DBusManager instance
is not destructed, so we avoid using already freed memory

make Manager::(un)serialize static functions, they don't depend on the instance state
No need to check for the NULLity of _dbus anymore

Remove a useless argument to initConfigFile

use dlerror() correctly

remove a few messages

sflphone-common -> daemon
sflphone-client-gnome -> gnome
sflphone-client-kde -> kde
sflphone-plugins -> plugins

Move all the code in a single .h file