~jaro/balkon

ref: 22f5b8331b78ed7f4bf318a36198a6ad4dd127fd 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.