~jaro/balkon

ref: 0f5dfa9a2b6865dc46ef926983c64b2ab11fa3d1 balkon/test d---------
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.