• [ttLib] Remove .Format from Coverage, ClassDef, SingleSubst, LigatureSubst, AlternateSubst, MultipleSubst (#2238).
  ATTENTION: This will change your TTX dumps!
• [misc.arrayTools] move Vector to its own submodule, and rewrite as a tuple subclass (#2201).
• [docs] Added a terminology section for varLib (#2209).
• [varLib] Move rounding to VariationModel, to avoid error accumulation from multiple deltas (#2214)
• [varLib] Explain merge errors in more human-friendly terms (#2223, #2226)
• [otlLib] Correct some documentation (#2225)
• [varLib/otlLib] Allow merging into VariationFont without first saving GPOS PairPos2 (#2229)
• [subset] Improve PairPosFormat2 subsetting (#2221)
• [ttLib] TTFont.save: create file on disk as late as possible (#2253)
• [cffLib] Add missing CFF2 dict operators LanguageGroup and ExpansionFactor (#2249)
  ATTENTION: This will change your TTX dumps!