Microtonal key signatures fix

[Graham Breed]

There's a long standing problem with unequally tempered key
signatures.  If the accidentals aren't halves, the MIDI production
fails.  I've worked out a fix.  Here's the diff from my system:

*** scm/midi.scm        2011/02/20 20:32:26     1.1
--- scm/midi.scm        2011/02/20 20:33:01
***************
*** 277,283 ****
  (define-public (alterations-in-key pitch-list)
    "Count number of sharps minus number of flats"

!   (* (apply + (map cdr pitch-list)) 2))



--- 277,283 ----
  (define-public (alterations-in-key pitch-list)
    "Count number of sharps minus number of flats"

!   (round (* (apply + (map cdr pitch-list)) 2)))



Sometimes this puts the wrong key signature in MIDI, but that's not
something I care about at all.  Rietveld shows the relevant code
hasn't changed.  It has moved to line 284.  At the weekend I'll look
at how to submit a snippet to show where the problem comes from.


                              t'other Graham