~jaro/balkon

ref: f93e69175a257cfbd5105b1d90baf535dd231c77 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.