Fixed error in README about creating config file.

README.org

@@ -14,7 +14,7 @@ go build
 mkdir -p /opt/kazoo_firewall_agent
 cp ./kazoo_firewall_agent /opt/kazoo_firewall_agent
 cp ./kazoo_firewall_agent.service /etc/systemd/system/
-cp ./kazoo_firewall_agent_config.json.sample /opt/kazoo_firewall_agent/
+cp ./kazoo_firewall_agent_config.json.sample /opt/kazoo_firewall_agent/kazoo_firewall_agent_config.json
 systemctl daemon-reload
 #+END_SRC
 *** Enable the Service