Gateway Bugfix Release

This release fixes minor bugs and is compatible with mainnet kava-4. There are no contraints on when validators should update.

Release Notes

• Increment version of the cosmos-sdk (to v0.39.2) and tendermint (to v0.33.9) to help an issue resulting in missed blocks
  for validators (tendermint/tendermint#5550).
• Add an authorized mempool feature to allow nodes to limit the transactions they accept into their mempool.