atm i am traversing the whole blockchain from genesis for each fetch instead getting the last high
to ensure consistency and prevent lost blocks within the db. blocks without 'nextBlock' are out this
way. additional i am running a cron to verify the chain every 10 min and rebuilt the db in-memory on
the fly, false blocks/transactions are deleted. not the best approach but ok until the peer is more stable.
ps: the checkpoints mentioned before acting as an additional cleaner, stucking at an orphaned block
invokes a jump back to the last good block in the checkpoint array. if this one fails too the fetcher
jumps back as long a good one is found or the genesis block is reached. in this case the blockchain-db
is built completely from ground again.
