should not interfere with popped up message boxes. Still there is a issue
with childs during splash startup: when one of them crashes with core dump
crash dialog will not be shown, but the main process handler correctly returns crash flag.
service_watcher() would not be drawn correctly yielding program hang since
add_fd() would not send events to fltk.
Also commented hack from Splash to keep it's window at the top of all;
now, using add_fd() evoke will get events before fltk which is what I want.
Not tested with other wm's.
Note: enabling that hack will surely crash evoke unless fl_handle() is removed
from main evoke loop.
without possible stealing from fltk. Prevous, add_handler(), would send only
unknown events for fltk which leave us without really important ones, like selection events
used by XSETTINGS manager.
Added XSETTINGS support (yet unfinished) which will make evoke as XSETTINGS manager.