~jaro/balkon

ref: 1fe9721d7be50e19e68cd8a8ec85f0adbb1c68e4 balkon/lib/Data/Text/ParagraphLayout/Plain.hs -rw-r--r-- 1.7 KiB 
Deprecate the Plain interface.

Add user data to spans.

Add line numbers to laid out fragments.

Qualify Plain interface.