[morx] "deleted glyph"?

[behdad]

Looks like morx fonts insert gid65535 as "deleted glyph". I think 1. we should associate the right class to that glyph (CLASS_DELETED_GLYPH = 2), and 2. delete them in post-processing, ie. replace with invisible_glyph.

[behdad]

I'm going to implement this, and use deleted-glyph during Ligature operations. That makes a difference in how some things (stack underflow) progress...

[behdad]

I'm probably going to delete them at the end of morx run, NOT leave it for default-ignorables to delete.