Server routing of client RPCs

Server can handle Client.Stats RPC

Client RPC Server

This PR enables the client to listen for new connections and then bind
an RPC listener to each connection in an upcoming PR.

Add demo TLS certificates and configs

Recognize renewing non-renewable Vault lease as fatal

Merge Community and Resources pages

Update Terraform configs to use latest versions of Consul, Vault and Nomad

remove duplicate typo

Fix HTTP code for permission denied errors

Fixes #3697

The existing code and test case only covered the leader behavior. When
querying against non-leaders the error has an "rpc error: " prefix.

To provide consistency in HTTP error response I also strip the "rpc
error: " prefix for 403 responses as they offer no beneficial additional
information (and in theory disclose a tiny bit of data to unauthorized
users, but it would be a pretty weird bit of data to use in a malicious
way).