Add Staff/part properties to Instrument right-click menu

[micpap25]

Resolves #11130

Define a function that creates a specialized right-click menu for instrument names, which contains the default right-click menu options as well as "Staff/part properties" after a separator.
This implements convenient functionality from MU3 and is useful for end-users.

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[RomanPudashkin]

Please, rebase your PR. There should be only one commit

[Jojo-Schmitz]

(IMHO) easiest way: git rebase -i HEAD~3, then replace the "pick" of the 2nd and 3rd commit with "f", save, then git push -f

[micpap25]

@RomanPudashkin Sorry about that, I've rebased. Thank you for the guidance @Jojo-Schmitz .