Add 4 lute fingering symbols to mscore font and to palette

This is in preparation of a more complete support for historic tablature to be added later.

The 4 symbols are added to the mscore font in the SMuFL code points. Currently, they are not correctly positioned, much like the other symbol-based fingering, i.e. the cello thumb position.

This is also to remind that further development of fingering layout will have to take into account that a number of fingerings are not really text but actually symbols.
Improve hinting
Leave glyphs in the font, but remove 3 (just added) Lute fingering symbols and the existing Thumb position symbol from the fingering palette.
Merge pull request #1182 from mgavioli/Addl_lute_fingerings_to_mscore_font_and_palette

Add 4 lute fingering symbols to mscore font / Remove Thumb from Fingerings palette