Extend Token Mark rule element to allow it to be referenced by other actors

[pedrogrullada]

Perhaps as roll options which allow to see the signature of the marker for uniqueness. This would go a long way to allow for a more thorough implementation of the Ranger's Hunt Prey, as well as perhaps the Thaumaturge when the system is ready to tackle it.

Quoting @xyzzy42's comment, which captures the idea of what I would want as well.

How about an extension:
TokenMark: "share": "allies"|"enemies"|"all"
Allow the specified group to also see this mark in their rolls against the target.

Roll options of this form are added:
target:mark:${mark.slug}:ally and target:mark:${mark.slug}:${mark.origin.signature}