Front-end logs can produce a huge amount of logs, with significant
duplication. In order to reduce the log volume, we truncate `nodeId` and
`channelId` in the MDC to only keep the first 8 hexadecimal characters.
Also, override a few `toString` because some channel-queries-related
case classes produce huge strings.
We now use a regular release zip, and use it in the awseb bundle.
The default logback configuration now logs to a file, like
`eclair-node`, and we use a dedicated logback configuration for AWS
beanstalk.
By default the front reads the node secret key from the node seed in
the standard `.eclair` directory.