* Set maximum time for nodes to be banned.
why:
Useless nodes are marked zombies and banned. They a kept in a table
until flushed out by new connections. This works well if there are many
connections. For the case that there are a few only, a maximum time is
set. When expired, zombies are flushed automatically.
* Suspend full sync while block number at beacon block
details:
Also allows to use external setting from file (2nd line)
* Resume state at full sync after restart (if any)
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