- neighbour nodes need to be contacted reliably
- Only holding NodeIDs requires a cache lookup for getting hostname and
port. This is brittle as the entry could've been purged from cache.
- refactored ASN.1 scheme, types and add/ sort/ remove implementations
closes#46
Motivation: Including the number of parts in each message part requires
the total number of parts to be known in advance, making dynamic
responses based on the received data difficult