API ping() uses an endpoint that is secured by ACLs

[dekimsey]

Issue

We were debugging an issue CONSUL_HTTP_TOKEN would cause the application not to start. We found the ping() call was hitting agent/self which requires the agent:read privilege. Our token does not have that privilege.

Solution

An ACL-less option for ping would be /status/leader or /status/peers which do not require an ACL to contact. I think this would better reflect the desired behavior of ping().