Dithering algorithms don't have internal variables for source and target, but they are provided as method arguments

EpilogDriver Fix: Wrong resolutions for EpilogZing. Also split a job if the parts have different resolutions

Changed Structure: DitheringAlgorithm, LaserCutter and LaserProperty implement the Customizable Interface. Thus Dithering-Algorithms can have Options (and are clonable)

- Deleted useless UnitTests (were interactive anyway)
- LAOS driver uses now floats instead of ints (untested)