Merge Hans' 1.0 version of nwc2ly.py into my new architecture.

Copy in Hans' 1.0 version of nwc2ly.py.

From
  http://lily4jedit.svn.sourceforge.net/viewvc/lily4jedit/trunk/LilyPondTool/otherpatches/nwc2ly/nwc2ly.py?view=markup&pathrev=457

Remove NWCToken_time_sig._sigs.

These were only used by previous versions to do relative durations,
and relative durations aren't worth the trouble.

Cleanup to more Pythonic sytax.

Add some example NWC 1.75 binary files.

1.75-1.nwc
  George Job Elvey: St. George's Windsor
  http://www.cyberhymnal.org/htm/c/o/comeytpc.htm
  http://www.cyberhymnal.org/mid/s/t/g/st_georges_windsor.mid
  basic piano tune
1.75-2.nwc
  Frederik Chopin: Fantasie - Impromptu
  http://www.keyboard-creations.co.uk/
http://t1b.co.uk/keyboard-creations/music/Chopin/fantasie.nwc
  moderately complicated classical piece
1.75-3.nwc
  Angels We Have Heard on High
  http://www.cyberhymnal.org/htm/a/n/angelswe.htm
  http://www.cyberhymnal.org/nwc/a/n/g/Angels%20We%20Have%20Heard%20on%20High.nwc
  lyrics
1.75-4.nwc
  Turlough O'Carolan: Thomas Burke
  http://www.oldmusicproject.com/occ/tunes.html
  http://www.oldmusicproject.com/occ/NWC/013-ThosBurke.nwc
  triplets and grace notes

Began versioning from nwc2ly.py v0.9.0

Downloaded from
  http://lily4jedit.svn.sourceforge.net/viewvc/lily4jedit/trunk/LilyPondTool/otherpatches/nwc2ly.py?revision=410&view=markup&pathrev=476