
- The "stop" button should move to the left of the progress bar,
  to free up room. More room for the main display means faster operation.
  
- Geometry border checkbox should actually draw a border.

- Assume the outmost paths are of an outline and use them to measure
  the board dimensions. This also means, board size should _not_
  use the thickness of the outmost paths.

- ToolpathNode should receive it's inch values in the constructor already.
  This would remove a lot of calls to ToolpathsProcessor.toModelX/Y.
  