Add 'hkna' and 'vkna' feature lookups

Actual glyphs will be added in near future.
Update 'vert' and 'vrt2'
Add 'hkna' and 'vkna' glyphs to pua-addenda.txt
Update Makefile
Merge branch 'kana' into hvkna

Update Makefile
Merge branch 'hvkna'

Add 'hkna' and 'vkna' features and glyphs