v2.4.0

New features

• Support for network-based configuration. When -config-source / CONFIG_SOURCE
  is set to network, Centauri will attempt to connect out to the address
  specified in -config-network-address / CONFIG_NETWORK_ADDRESS. The initial
  config must be provided within 10 seconds of connection, and then any future
  updates can be pushed as needed. The protocol is documented in
  docs/network-config.md.