Feat/message/mempool

[oxlime]

closes #82
Added mempool.zig, implementing necessary functions to deserialize/serialize into the wire
Added some tests but should look similiar to Verack as neither contain payload.

[tdelabro]

You should also add it as an if/else condition in wire deserializeMessage

[oxlime]

You should also add it as an if/else condition in wire deserializeMessage

should be good now i just forgot to git add that file.

[oxlime]

You should also add it as an if/else condition in wire deserializeMessage

https://github.com/oxlime/btczee/blob/cae11b088a2b052dc768b84612eb503f81b52005/src/network/wire/lib.zig#L83

[tdelabro]

oh I missed it sorry