update to the latest, simpler p2p spec

[CHr15F0x]

Fixes: #1717

"Old" style p2p sync client removed along with the parser module. Delta is big because the changes in dtos are significant. Thus the capability to sync from other nodes is temporarily missing until streams are implemented for all protocols.

There's at least 3 things I'd like to do in followup PR-s that are missing here:

• decrease the message size limit on the wire to 4MiB for classes and 1MiB otherwise,
• compute the address field of Deploy transactions,
• use fluke channel in sync handlers to pass items as they are read without intermediate collection into Vec.