~jaro/balkon

ref: 1c4f51d85e470cec31f12e4173c9985de3c554e3 balkon/src/Data/Text/ParagraphLayout d---------
Use CSS-compatible line height settings.
Upgrade Fragment to contain pen position.
Use CSS3 terminology for fragments and containing block.
Avoid reimplementing Data.Text.Lazy.fromStrict.
Implement "plain" interface.
Use Rect in "plain" interface.
Create "plain" interface.
Add module for working with rectangle coordinates.
Separate modules.