General fixes:
=============
+- AAT 'morx' implementation.
+
+- Return "safe-to-break" bit from shaping.
+
+- Disable 'vert' if 'vrt2' is available (eg. Motoya fonts with arrow chars).
+
+- Fix TT 'kern' on/off and GPOS interaction (move kerning before GPOS).
+
+- Implement 'rand' feature.
+
- mask propagation? (when ligation, "or" the masks).
- Warn at compile time (and runtime with HB_DEBUG?) if no Unicode / font
funcs found / set.
-- Fix TT 'kern' on/off and GPOS interaction (move kerning before GPOS).
-
- Do proper rounding when scaling from font space? May be a non-issue.
- Misc features:
* vkna,hkna etc for kana, etc
* smpl,trad for ZHS / ZHT
-- Add ICUlayout API?
-
API issues to fix before 1.0:
============================