Resolve "Alt+DoubleClickLeft also triggers Alt+ClickLeft"

This MR changes the shortcut for jumping to a frame from Alt + DblClick to Ctrl + Alt + DblClick and differentiates between Alt+Click and Ctrl+Alt+Click to resolve issue #328 (closed)

This way, only the jumping, without the changing of the trackpoint, gets activated,

Closes #328 (closed)

Reviewer Checklist

General code quality

• naming conventions are met (see .clang-tidy for detailed information)
• no static analyzer warnings in new code parts (e.g., use clang-tidy for checking)

General usability

• old versions of pet-files are still loadable

Only if changes in UI

• new elements are also saved and loaded from pet-file
• check if tab order is still correct
• all new SpinBoxes are promoted
• new keybindings added to Petrack::keyBindings()

added bug label

changed the description

requested review from @t.schroedter

marked the checklist item naming conventions are met (see .clang-tidy for detailed information) as completed

marked the checklist item no static analyzer warnings in new code parts (e.g., use clang-tidy for checking) as completed

marked the checklist item old versions of pet-files are still loadable as completed

marked the checklist item new elements are also saved and loaded from pet-file as completed

marked the checklist item check if tab order is still correct as completed

marked the checklist item all new SpinBoxes are promoted as completed

marked the checklist item check if tab order is still correct as incomplete

marked the checklist item new elements are also saved and loaded from pet-file as incomplete

marked the checklist item all new SpinBoxes are promoted as incomplete

marked the checklist item all new SpinBoxes are promoted as completed

marked the checklist item check if tab order is still correct as completed

marked the checklist item new elements are also saved and loaded from pet-file as completed

Keybinding needs to be changed in Help -> Key bindings. Rest looks good!

added 1 commit

• 5be14118 - Update Keybindings description

Compare with previous version

marked the checklist item new keybindings added to Petrack::keyBindings() as completed

added 5 commits

• 5be14118...b0eb653a - 2 commits from branch master
• b4c18b2c - Change Shortcut for jump Alt+DblCLick to Ctrl+Alt+DblClick
• 2895030f - Only fire mouseAltPressed event if Ctrl wasn't pressed as well
• d3a2575f - Update Keybindings description

Compare with previous version

enabled an automatic merge when the pipeline for d3a2575f succeeds