Changes file for the 2015 series

This reflects changes to MMA since the release of version 15.01.

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Added macro variables $_Track_Delay, $_Track_HarmonyOnly,
  $_Track_MidiVolume and $_Track_StrumAdd.

Fixed bugs in GRACE notes. When fixing the code which ensured that all
  the notes in a chord ended up with the same duration, we forgot that
  GRACE notes were supposed to be different. Well, they are now!

Harmony was NOT being applied to chords with grace notes. Fixed.

Solo note volume adjustments weren't working properly.

February 8, 2015
Released 15.01a

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Added RPITCH command. Modifies notes on-the-fly for random "mistakes".
 Actually makes some bass lines, etc sound quite natural. See the
 docs for details.

Added donated instrument file for Roland-mt32 in includes. Thanks 
 so much Hanno Behrens!

Added alternate spelling for TRANSPOSE and LYRICS TRANSPOSE. Both now accept
 interval syntax like "Up Minor Third", etc.

May 13, 2015
Released 15.01b

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Added Subroutines. See the manual for details. This could be quite useful.


May 19, 2015
Released 15.01c

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Fixed Transpose so that "Up Major 2" is the same as "Up Major Second".

Fixed the warning messages for slash chords so that things like C/B
 do not print warnings. The manual for slash chords has been
 (hopefully) clarified.

In the manual and code the COMPRESS option took values 0 (off), 1, ... 5.
 I have no idea why. The actual code only compresses once and the value
 is ignored. Docs and code are updated to reflect reality.

July 10, 2015
Released 15.01d

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Added Lyric option On or Off.

Fixed import error for python3.

Added fretnoise option in plectrum tracks. See the docs and a short
 example in egs/misc.

August 29, 2015
Released 15.01f

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Added -L option to report label/lines proceesed order.

CHANGED fretnoise strings are now numbered in the correct mode.
 String 1 is the highest sounding, just like a real guitar.

BUGFIX: fretnoise now looks for chord change instead of just string change.

September 9, 2015
Released  15.01g

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Modified -L option to show '?' for bars without labels.

Fixed MIDIINC which was crashing when importing a file with lyrics.
