Enable nineteen more warning options so that more warnings can be detected

After applying latest commits: in order to show more warnings in new developments, nineteen warning options can be added to the Krusader building process.

New warning options were obtained from the ones recommended on https://www.asc.ohio-state.edu/physics/ntg/6810/handouts/recommended_C++_options.pdf and https://wiki.qt.io/Coding_Conventions, those options were not included:

• -Wold-style-cast and -Wshadow because they caused too many warnings in the current source code of Krusader;
• −fshort−enums because it caused warnings in code like setFrameStyle(QFrame::HLine | QFrame::Sunken), Qt::CTRL + Qt::Key_L or Qt::CTRL | Qt::Key_L.

Also, other useful warning options were added: -Wlogical-op -Wuninitialized -Wredundant-decls -Wnoexcept -Wnon-virtual-dtor -Wctor-dtor-privacy -Wzero-as-null-pointer-constant.

If this MR is merged, I can also register some issue reports on https://invent.kde.org/utilities/krusader/-/issues so that Krusader can end up using warning options like -Wshadow. Also, solving some parts of one of those issues can be useful as a "junior job" for new developers who want to get practice with Krusader.