Fix outsideSize to work for just bottom,right clues, too.
Add areaGrid primitives to DSL.
Add cell-aligned outside clue primitive.
Add standalone renderer for 'Summon'.
Messing around with outside clue placement.

This will remain broken until I figure out a clean way to
distinguish between cell and vertex placement.
Update Foldable instances from 'fold' to 'foldMap'.
Remove unused import.
Improve librarization of command-line helpers.

- Kill redundancy between drawpuzzle.hs and CmdLine.hs.
- Isolate CPP backend configuration to one file.
Fix outside clue test by simplifying, as usual.