InstrumentFunctions: added natural minor scale

A natural minor scale was missing which lead to some irritations about
the harmonic and melodic minor scales. Had to add the new scale at the
end of the chord table in order to not break existing projects and
presets in which simple chord table indices are saved.

Closes #3594824.

src/core/InstrumentFunctions.cpp

@@ -130,6 +130,7 @@ ChordCreator::ChordTable::Init ChordCreator::ChordTable::s_initTable[] =
 	{ QT_TRANSLATE_NOOP( "ChordCreator", "Mixolydian" ), { 0, 2, 4, 5, 7, 9, 10, -1 } },
 	{ QT_TRANSLATE_NOOP( "ChordCreator", "Aeolian" ), { 0, 2, 3, 5, 7, 8, 10, -1 } },
 	{ QT_TRANSLATE_NOOP( "ChordCreator", "Locrian" ), { 0, 1, 3, 5, 6, 8, 10, -1 } },
+	{ QT_TRANSLATE_NOOP( "ChordCreator", "Minor" ), { 0, 2, 3, 5, 7, 8, 10, -1 } },
 } ;