* re-introduce static pattern cache
(cairo's cache is not nearly large enough for A3 + plugins)
* only use cairo_clip on rectangles (not arbitrary paths
-> major performance boost
* re-add fader pixel reserve
* fix mouse + scroll interaction
* fix unity line display (1px wider, brighten by 150%)
* cache text size
* fix various other issues and consistent whitespace
This reverts large parts of commit d439e93b1e.
9f0caacc5c