feat(p2p): add snappy compression to p2p messages

[Maddiaa0]

Overview

P2P messages are currently sent as raw buffers, but they can be compressed.

Ethereum opts to use snappy compression for the propagation of p2p messages (https://github.com/google/snappy), although it is not a perfect compression algorithm it runs very very quickly.

We should see a large improvement here when propagating transactions as although they contain "random" data, they have G1 Points encoded over 4 field elements ~508bits, when they are only ~256 bits each. ( This is done as the points are encoded as Fr scalars, that can be directly used in transcript hashing ).

Add snappy compression on all p2p sending functions

• in propagate of p2p client
• in send of reqresp

Add snappy decompression on receipt

• in processFromPeer of p2p client
• in recieve of reqresp