Show route style clearance

[David Austin]

I wish that the DRC clearance options in the settings menu ('Crosshair shows DRC clearance' and 'Auto enforce DRC clearance') could (optionally) use the Route style parameters instead of the DRC parameters. The DRC parameters are the absolute minimums for manufacture, but generally route styles have different parameters - particularly the minimum track spacing which is useful with the auto enforce DRC clearance setting.