[Denemo-devel] Fix for coredumping on loading file with keysig change in first measure

[Richard Shann]

I have a fix for this, (see the thread
Re: [Denemo-devel] coredump loading score containing clef change in
first measure)
 which I came across in the course of creating the movement handling
code. This is mostly finished now - it also fixes another coredump:
         timesig changes that are made in measures which are lacking in other
staffs coredump.
I'll check in as soon as I'm confident I haven't damaged anything really
mainstream.
Richard