use GLibs main_loop (x11 part)

this is WIP since the dbus part is missing
Basic dbus functionality reintroduced
remove some debugging printfs
improve responsiveness
reintroduce fgcolor/bgcolor hints
onCloseNotification
notificationClosed (not working yet)
remove debugging printfs
onCloseNotification send reply
remove more debug prinfs
add glib to dependencies in INSTALL
fix compile warnings