Implement soft stop in Consenter #368
Description
Once a config block is delivered as a first step we would like to stop the consenter and let the admin restart it with the new config.
However, currently the consensus stop method does a hard stop and closes everything, including delivery service used by the router, batcher and assembler.
If we use this stop method in this case the assembler and batcher will not get the config update from the consenter.
In addition, lagging consenters use "Sync" which also consumes from the delivery service.
Therefore, we suggest introducing a "soft stop" to keep what is needed open.
Soft stop will close everything except the delivery service, and will emit a Warning log line the says "Soft stop: pending restart".