~jaro/balkon

ref: f93e69175a257cfbd5105b1d90baf535dd231c77 balkon/test d---------
Clean up ParagraphConstruction.
Use infix operators for constructing test data.
Implement "plain" interface.
Create "plain" interface.
Add module for working with rectangle coordinates.
Add explicit scale to test font.
Automatically discover test specs.
Separate tests by module.
Add unit tests for spanToRuns.
WIP version with WIP interface.