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 search page function, make navigator aware of page offset
fix import of copyright from MIDI and GP
remove options to change copyright and fraction symbols automatically
fix #25254: XML export from 1.3 with & in text causes MSCZ corruption
try to fix issue #25255, network path for Documents folder on Windows
fix #25229: Some dynamics have too much internal space (no kerning)
set staccato to 50 for all instruments, set gatetime for all pianos to 95, flute too as a try
slur playback for the whole staff
fix #25281: handling of some slash chords
fix #25209 MusicXML reloads with measure actual as 1/1
Merge pull request #821 from lvinken/musicxml-fixes

fix #25209 MusicXML reloads with measure actual as 1/1
Merge pull request #820 from MarcSabatella/25281-slash-chords

fix #25281: handling of some slash chords
fix #25112 export slur on grace notes
fix #25254
Alternative recursive tuplet filtering algorithm
O(1) instead of O(log N) tuplet indexes exclusion
Small optimization in tuplet exclusion
Add save/restore functions for valid tuplets