Log Message:
py-fonttools: updated to 3.19.0

3.19.0:
[varLib] Try set of used points instead of all points when testing whether to \ 
share points between tuples.
[CFF2] Fixed issue with reading/writing PrivateDict BlueValues to TTX file. Read \ 
the commit message 8b02b5a and issue 1030 for more details. NOTE: this change \ 
invalidates all the TTX files containing CFF2 tables that where dumped with \ 
previous verisons of fonttools. CFF2 Subr items can have values on the stack \ 
after the last operator, thus a CFF2Subr class was added to accommodate this.
[_k_e_r_n] Fixed compilation of AAT kern version=1.0 tables
[ttLib] Added getBestCmap() convenience method to TTFont class and cmap table \ 
class that returns a preferred Unicode cmap subtable given a list of options.
[morx] Emit more meaningful subtable flags. Implement InsertionMorphAction