~jaro/balkon

ref: cf3ec3e35ebdbbe540c0a1490545622157271543 balkon/src d---------
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.
WIP version with WIP interface.