[Feature Request] Add option to add additional distance when passing through tokens

[nschoenwald]

In systems like dnd5e, passing through friendly tokens counts as difficult terrain. So passing a grid square with a token in it should count as two squares (ten feet). It would be great if the module could include this in the calculation and even better if it was configurable in the options.

Elevation ruler has this functionality, but I don't need the elevation related functionality and prefer drag ruler for its ease of use: https://github.com/caewok/fvtt-elevation-ruler