Changed removal of spanner in range selections.
Slurs are removed when start or end segment are removed.
Other spanners are removed if the start segment is removed.
Added test suite for selection range delete.
Added tests for range delete of spanners, and slurs.
Changed highlighting for spanners.
Hide naturals in key signature
Revert to long instrument name if no short name
Allow both Shift and Ctrl drag modifiers.

At least for bar line dragging, Shift-dragging can co-exist with Ctrl-dragging: allow detection of either, if both.
Fix merge conflict and modif. check for bar lines separate from other elements.
TAB entry mode: Sync current note with string cursor.

In TAB entry mode, while moving the string cursor up or down, the current (selected) note remains the last inserted note, with the following inconsistency:

- new notes are entered at the string cursor
- but cmds affecting a note (pitch up/down and like) changes the selected note;

this is likely to lead to confusion and unexpected results.

With this fix, when the string cursor is moved up/down and a note is found at the new string, it is made current (selected). If there is no note, the selection remains unaffected.

Note: Also corrected a typo in the name of a StaffType method.
export correct creditwords justify and valign attributes
fix #26776
fix #26971: Seek now works after repeat
fix #26966: 'Play repeats' button works
fix #26586
Merge pull request #1014 from vgstef/ContinuousPanel

Continuous panel
Merge pull request #1018 from lvinken/25193-musicxml-text-formatting-4

export correct creditwords justify and valign attributes
Merge pull request #1017 from Igevorse/repeat-error

fix #26971: Seek now works after repeat
Merge pull request #1015 from Jojo-Schmitz/warnings

fix typo in cmake file
Merge pull request #1009 from mgavioli/Both_shift_and_ctrl_drag_modifiers

Allow both Shift and Ctrl drag modifiers.
Merge pull request #993 from BartlomiejLewandowski/range-selection-spanner-delete

Range selection spanner delete
Merge pull request #1016 from mgavioli/Sync_strg_cursor_and_curr_note_in_TAB_entry_mode

TAB entry mode: Sync current note with string cursor.