[Feature request] Border Gates, Quest Guards and Quest Gates

Border Gates (or something similar that requires a H2 Wayfarer's Tent, that doesn't disappear) and Quest Guards (that do disappear) such as in H3 and H4, and Quest Gates (that don't disappear) such as in H4.  Quest Guards and Gates require a particular condition to be able to open or go through, and Border Gates (or equivalent) require a Wayfarer's Tent of that colour to be visited.

It should be pretty easy to make a new kind of border guard that can only be passed when a certain condition is met, and I'm interested in building them soon after the map editor overhaul makes it easier. Gates are harder, but I'd like them.