Remove area protection checks

[Niklp09]

Closes Archtec-io/bugtracker#194
Concept approved by SwissalpS.

[SwissalpS]

LGTM (without testing) I like this.

It does make me wonder if later on we might PR a protection check hook for server-mods to more easily override checks to their liking. e.g. staff privs, factions and shared ownerships.

I'd like to keep checks in the mod minimal and easy to read but some servers might want more complicated checks. Giving a hook would allow them to have messy code on their end and the [travelnet] could stay clean.

[SwissalpS]

check hook could have a signature like function travelnet.protection(pos, player, context) where context is a string or 'enum' for one of: remove, edit, first setup.
optionally node could also be passed so that doesn't need to be looked up again.

I don't think a .register_check(f) type of hook is needed here.

[SwissalpS]

partially addresses #31

[BuckarooBanzay]

lgtm 👍