Fix #25165 - crash when changing rest measure duration to or from irregular time.

When the actual duration of a measure is changed and either the starting or ending duration cannot be represented with a simple value (for instance 5/4) and the measure contains a single whole measure rest, a division by 0 results. See http://musescore.org/en/node/25165 for examples, discussion and analysis.

Fixed.

If the new measure value is different from the current time sig, rest(s) to represent the actual measure values are used instead of whole measure rests.
Tick where to place the newly added rests was wrong.
fix #25112 export slur on grace notes
fix #25112: import slur on grace notes
fix #25424: ottava playback solved
Added new constructor for parts, removed unnecessary calls to
setParentScore.
Fixed test scores by removing redundant metaTags in parts section.
fix #25454: unisons should share noteheads despite duration difference
fix #25246: line properties for voltas
fix #25384: grace note spacing
Support for voltas in GP5 files
Updated volta test to remove additional staff types; Updated iteration declaration to use auto keyword
fix #25456: Spurious key signatures appear when layout changes
Merge pull request #853 from jpirie/22898-guitar-pro-volta

Progress on #22898: Support for voltas in GP5 files
Merge pull request #852 from MarcSabatella/25384-grace-note-spacing

fix #25384: grace note spacing
Merge pull request #851 from MarcSabatella/25246-volta-line-properties

fix #25246: line properties for voltas
Merge pull request #850 from MarcSabatella/25454-unison-voices

fix #25454: unisons should share noteheads despite duration difference
fix #25394, fix #25457: do not sort notes in chord while looping through notes in chord
Merge pull request #848 from BartlomiejLewandowski/25283-partscopyright

25283 partscopyright
Merge pull request #841 from LucaRood/25424-ottava

fix #25424: ottava playback solved