This service is a basic in-memory key-pair cache. It is used by the Dogebox (by default) to persist its local, internal IP address somewhere that the users client can find it once the Dogebox has switched networks.
Fetch the IP submitted via token. Is a one-shot fetch, will be removed after you have retrieved it.
Return 200 { "ip": "1.2.3.4" } if found.
Returns 404 if not found.
Required body: { "token": "abc", "ip": "1.2.3.4" }
Returns 201 on create.
Rate limited to 1 per minute via IP.