The scenery camera is set up by the driver mode, which never runs when the
exe starts straight in the editor - the editor then copied an untouched
global camera and rendered a black view with only the UI on top. Entering
the editor as the startup mode now initialises the camera itself, falling
back on a view above the origin for sceneries that name no camera, and
resets the timers so the loading time does not land in the first frame.
The editor was reachable only from the driver mode with F11, which meant
loading a scenario and starting the whole simulation first. With -editor
the scenario loader hands over to the editor instead of the driver, so
physics, AI and timetables never run - only the loaded world is there to
be worked on.
Without -s the scenery from eu07.ini is used, falling back to pusta.scn
when the ini names none. F11 quits instead of popping the mode, since the
editor is now the bottom of the mode stack and popping it would leave the
rest of the frame reading an empty one. Editor entry forces free-fly even
with no vehicle to leave.
