fix #25765 : Fix crash when clicking bar time

setScore() was overridden to an empty function
so the score was never set. Now using the setScore()
inherited from MuseScoreView
Open strings in StringData.

Allows to mark strings as open (non-fretted).
Defaults to fretted, keeping backward-compatibility with existing scores.
Adds an attribute `open="1"` in score (and instruments.xml) string data (defaults to "0").

Benefits:
- allows future support (also in TAB's) for string instruments with non-fretted strings (mainly but, I think, not only the lute family)
- gives correct fretting for non-fretted strings
- instrument range can more easily and automatically linked to actual string tuning
- as this will be eventually needed for better TAB support, the score reading/writing will be already able to manage it.
Small cosmetic changes to mscoreTAB fonts
fix #28356: add MuseJazz as a musical text font
remove code duplication in InstrumentsDialog and NewWizard
Refactoring and improving playback on GPX format - improvements to importing percussion still need to be made (drumset)
Support for ties, grace notes and some articulations in Guitar Pro 6, Guitar Pro implementation split up.
Added support for double bars in Guitar Pro 6
Support for trills, crescendos and diminuendos in the Guitar Pro 6 format
Support for Guitar Pro 6 tremolos
Added support for GP6 wah open and wah close
Support for dynamics, accents, turns, mordens and pick directions in Guitar Pro
Fingering supported in GP4, GP5 and GP6
Support for arpeggios, voltas, brush markings, grace notes (on and before beat) and repeat markings
Added palm mute text
Support for let ring marking in GP4/5/6
Support for tapping, slapping, popping, barre, timer and text markings
Support for artificial harmonics in Guitar Pro 6
Added support for parenthesised notes in Guitar Pro 6
Support for rasgueado marking in GP6