~jaro/balkon

ref: cf3ec3e35ebdbbe540c0a1490545622157271543 balkon/src/Data/Text/ParagraphLayout/Internal/WithSpan.hs -rw-r--r-- 1.2 KiB 
Move BiDi Level to separate module.

Allow extracting ResolvedBox from WithSpan.

Separate WithSpan for sharing with other modules.