README update links
Mozart: move notes to separate file
Sibelius 7: move notes to separate file
add Dave's addendum about final barline
Syntax and major changes

Herein adherence changes to the main branch, with respect to a further
file change and re-organization.
Merge pull request #4 from joshdnichols/master

Josh's Finale version update
update to more recent development version of MuseScore
refine slurs
add PDF files for earlier stages