rm many unused fcts, detected with xunused

detected using xunused (described in Developer's corner).

enabled an automatic merge when the pipeline for 91725503 succeeds

aborted the automatic merge because source branch was updated

added 5 commits

• 7ec0c77e - rm VariantUtil
• 21c8b641 - rm mumufit::utils::numbersDiffer
• 763a570c - rm unused fcts from AppOptions
• a8c4b8db - rm includes; rm unit related fcts
• b8b15f14 - rm fct

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changed the description

added 3 commits

• 33f2abfe - rm TestMinimizerPlan
• 8adcc6b6 - SciSpinBox rm getters
• c9b17a27 - rm various unused fcts

Compare with previous version

enabled an automatic merge when the pipeline for c9b17a27 succeeds

mentioned in commit fe0fcc11

merged