~jaro/balkon

ref: b7e2da83c6eaeb921f5113e58f2f1fa4e580e292 balkon/src/Data/Text/ParagraphLayout/Internal/ParagraphExtents.hs -rw-r--r-- 925 bytes 
Allow paragraphRect without point 0,0.

Parametrise rectangle union bias.

Separate interface-independent constants.