The crystal http client maintains a keepalive connection to the other
server which stays alive for some time. This should be closed if the
client instance is not used again to avoid hogging resources
Everything that gets logged now has a log level associated with it.
The log level can be set with the new `-l` or `--log-level` arguments.
The defaul log level is `debug` for now. There aren't many things that get
logged but if the logs get spammed in the future it can be set down to `info`.
