Attempt to write a Tuxguitar plugin to import Songsterr JSONs.

You need to install the TuxGuitar lib to a local repo inside this project:

mvn \
  install:install-file \
  -Dfile=$path/tuxguitar-lib.jar \
   -DgroupId=app.tuxguitar \
   -DartifactId=tuxguitar-lib \
   -Dversion=9.99 \
   -Dpackaging=jar \
   -DlocalRepositoryPath=$thisDir/songsterr/repo/