Log Message:
abcmidi: update to 20210525

May 22 2021

abc2midi: treble-8 not applied in K: or V: commands after October 19 2020
update. For example,

X:1
T: transposition
L:1/2
M:C
K:none clef=treble-8
V:1
cz
V:2
zc

The note c should be played with midi pitch 60 instead of 72.
James Allwright made minor fixes to parseabc.c and store.c, in order
to get these options working again.

May 25 2021

James Allwright added more security checks to stop the
parser from reading numbers beyond the largest integer. Changes
were made to parserabc.c and midi2abc.c

The abc2abc -s spacing function was modified to ignore certain
time signatures like M: none or M:7/8. The code for dealing with
3/2, 3/4, 3/8 ... time signatures was improved.