ufo-kit/concert — pull request #31 by matze (2013-08-19 09:19:51+00:00)
Title: Guess unit from calibration

This change tries to fix #19. For this

- I added explicit user and device unit fields to calibrations.
- I added `numerator_units()` and `denominator_units()`.
- Renamed `to_steps` to `to_device`, because not all devices might have a notion of a step.
- Removed implicit dropping of units from `to_device`.