Doh! Really fix retry count handling!
Dirty hack fix for infinite loop when ignore last block.
Explain.
Don't choose to fetch the last data block for really old splitfiles. We may still pick it up by accident however.
Use KeysFetchingLocally to not schedule a fetch for a key that is currently being fetched.
Ignore failure on blocks already found (race condition?)
Fix stalling counting bug in 647ad6c60c76209fd77f5cad120aec9415607573 - requests for old keys would stall forever.