Implement server url info to the about method in cli_wallet

Closes #285 (closed)

• Implemented server url info to the about method in cli_wallet

New output preview:

{
  "blockchain_version": "1.26.0",
  "client_version": "20220825_auto-11-g6353392bd",
  "hive_revision": "6353392bd0c4e10e8d673e8c1b1844d13e0b1ca2",
  "hive_revision_age": "47 seconds ago",
  "fc_revision": "6353392bd0c4e10e8d673e8c1b1844d13e0b1ca2",
  "fc_revision_age": "47 seconds ago",
  "chain_id": "18dcf0a285365fc58b71f18b3d3fec954aa0c141c44e4e5cb4cf777b9eab274e",
  "compile_date": "compiled on Aug 26 2022 at 17:53:52",
  "boost_version": "1.71",
  "openssl_version": "OpenSSL 1.1.1f  31 Mar 2020",
  "build": "linux 64-bit",
  "server_blockchain_version": "1.26.0",
  "server_hive_revision": "938f783479befae8e6e12fa2c74138a962b0ea55",
  "server_fc_revision": "938f783479befae8e6e12fa2c74138a962b0ea55",
  "server_chain_id": "18dcf0a285365fc58b71f18b3d3fec954aa0c141c44e4e5cb4cf777b9eab274e",
  "server_url": "ws://127.0.0.1:8090"
}

(note the server_url property at the end)