SharpFont/FreeType backend does not like non-ascii filenames

[HinTak]

This was filed upstream around when FontVal 2.0 was in testing about a year ago:
Robmaister/SharpFont#89

This was fixed two months ago:
Robmaister/SharpFont#112

and backported:
Robmaister/SharpFont#89 (comment)

This is mostly a note to for people who are still using 2.0 to upgrade as soon as 2.1 is out.

[HinTak]

Two-part fixes in the upcoming v2.1 .

[HinTak]

change unhooked with 2.1 due to instability.