Fix syntax error reported by build system: can't mix string string types when doing literal concatenation
Fix local import reference - doesn't work in Python3.
Addressed issues raised by @msousa for PR 1345 yesterday.
Will change cff2_merge_funcs.py and cff2mergePen.py from tab to space indentations after the current comments are resolved.
Add various improvements from comments:
- do not edit the post table under varLib.build(). Setting post table format 2 or 3 is now expected to be managed by whatever calls varLib.build().
- In the t2CharStringPen module, rename closure _round() nested in makeRoundFunc to an exportable function, and use it in cff2mergePen.
- remove TypeSupply copyright from cff2mergePen.
- use modulo function to convert float to int when it is meant to be 0 in cff2mergePen.
cff2_merge_funcs.py:merge_PrivateDicts() should only be blending the hint related fields in the PrivateDict. This oversight that was surfaced by @madig reporting an error building his Cantrell font. The bug appeared when the font was subroutinized, as the pen draw method then has to interpret the Subr field in order to access T2Charstring subroutines.
Fix expected ttx output file. When I removed the logic to add glyph names to the post table, glyph names in the ttx file changed.
Miguel prefers a simple list for readability in cff2_merge_funs.py:138.