update RPC communication to use :8551 and JWT token

[donpdonp]

Running geth 1.12.1, the http user/pass is gone and --authrpc.jwtsecret /tmp/jwtsecret is used instead. This unfortunately makes eth-cli useless for a local geth server. The update looks simple, add a Authorization: Bearer $TOKEN header to the rpc request.

https://github.com/jwasinger/geth-jwt-example/blob/master/curl_example.sh