Update to sdk v0.39.x

[rhuairahrighairidh]

Changes (to kava):

• remove the monkey patch in cmd/kvd that disabled pruning=syncable. The new pruning options are default, nothing, everything
• merged in the fix for the cli tests from Fix cli tests #609, added a new test for sending multiple transactions per block (in cli_test/)
• updated the json serialization of ValidatorVestingAccounts to match the new format in v0.39

Changes in v0.39: https://github.com/cosmos/cosmos-sdk/blob/v0.39.1/CHANGELOG.md

Tests:

• Ran a 4 node local testnet (with a script that continusously sent ~16 txs per block) and restarted 1 node 20 or so times with varying pruning configs. Could not replicate the previous issue: Logical Commit(s) are not Atomic cosmos/cosmos-sdk#6370. I was able to replicate the issue by restarting the node many times on kvd v0.10.0.
• Ran MsgSend and MsgCreateCDP with cosmos ledger app

Todo for external parties

• validators will probably want to update their app.toml pruning config (in most cases to pruning=default)
• rest consumers who query accounts will need to update - notably account numbers and sequences are now strings rather than numbers
• Any workarounds around not sending multiple txs per block can be removed now.

TODOs (for later PRs)

• write migrations to transform 38 account json into 39 json
• update swagger (and rest tests?)