[Inkscape-devel] nudge distance, cursor tolerance

1. Nudge distance is now stored in preferences. Default is 1 mm, let me know if you think this value needs to be changed. This affects arrows and shift-arrows in selector and node edit. No GUI to change that value yet, but you can edit your preferences.xml to test.

2. Cursor tolerance (from display options) is now stored in preferences too. I changed default from 1.0 to 2.0, but perhaps it should be made even bigger. This affects how close you need to be to an object to grab it; bigger values make the tools much more usable, especially with a tablet. Please test and report what value works best for you (I like it at 8.0), then we'll take the average and make it the default :)