Tari core developer update

It's been a few hairy weeks since the last update. We had testnet stop for a while and saw some large reorgs since adding merge-mined Monero blocks to the chain. Although the large forks weren't intended, it allowed us to find and fix a number of bugs. There's still some work to be done, but the network is getting more resilient all the time.

Here are some of the highlights since v0.5.3

• Many fixes and updates to tari_merge_mining_proxy. This program proxies requests from RandomX miners to monerod in order to allow mining tXTR and Monero at the same time.
• Implement transaction negotiation message resending in the wallet.
• Implement LMDB automatic resizing during sync.