major step towards the new design
fix testbackend, make isdirty(),isstatic() abstract
remove gtkmm backend (would be a horrible hack).
cleanup testbackend add xbackend  stub
join constdef and confread to configbackend
fix xbackend
redesign of rendering infrastructure (let backend implement it), some progress in X backend, rename sdlfiles
x can create a window, add xroutines for helproutines
create window in x, rename countviewports in amount_viewports, other changes
use int32_t type, make Xbackend working, improve handle_event, use getopt (and homegrown solution because of strange getopt behaviour),replace MASTER_HANDLE,… by backend by actions,add possibility to change display
exit: exit via exceptions so a cleanup is possible, implement RELOAD_DE and QUIT_DE
really unstable commit: add label