Vestax VCI-300: Adjust and fine-tune parameters

No complaints so far:
http://www.mixxx.org/forums/viewtopic.php?f=7&t=4021&start=30#p20070

Is it just coincidence that the release notes of Serato DJ 1.5.2 mentions "Fixed the platter resolution on the Vestax VCI-300"? ;)

- Exactly measured the and adjusted jog resolution
  parameters. It's only 1600 instead of 1664 steps per
  revolution!! This was wrong since the initial version :(
- Synchronized jog feedback between scratching and cueing
  by using a linear response
- Slightly increased sensitivity for jog scrolling
- Some code cleanup