add migration guide for v16 (#1128)

* feat: add migration guide for v16

* fix: title

migrate/v0_16/migrate.md

@@ -0,0 +1,100 @@
+# kava-9 Upgrade Instructions
+
+## Software Version and Key Dates
+
+- We will be upgrading from chain-id "kava-8" to chain-id "kava-9".
+- The version of Kava for kava-9 is v0.16.0
+- The kava-7 chain will be shutdown with a `SoftwareUpgradeProposal` that activates at block height __1803250__, which is approximately 14:00 UTC on January, 19 2022.  
+- kava-9 genesis time is set to January 19, 2022 at 16:00 UTC
+- The version of cosmos-sdk for kava-9 is v0.44.5
+- The version of tendermint for kava-9 v0.34.14
+- The minimum version of golang for kava-9 is __1.16+__.
+
+__NOTE__: As part of the upgrade to kava-9, the `kvd` and `kvcli` binaries were combined into a single blockchain binary named `kava`. When restarting the chain, be sure to use `kava start` and not the deprecated `kvd start`. 
+
+### Risks
+
+As a validator, performing the upgrade procedure on your consensus nodes carries a heightened risk of double-signing and being slashed. The most important piece of this procedure is verifying your software version and genesis file hash before starting your validator and signing.
+
+The riskiest thing a validator can do is discover that they made a mistake and repeat the upgrade procedure again during the network startup. If you discover a mistake in the process, the best thing to do is wait for the network to start before correcting it. If the network is halted and you have started with a different genesis file than the expected one, seek advice from a Kava developer before resetting your validator.
+
+### Recovery
+
+Prior to exporting kava-8 state, validators are encouraged to take a full data snapshot at the export height before proceeding. Snap-shotting depends heavily on infrastructure, but generally this can be done by backing up the .kvd and .kvcli directories.
+
+It is critically important to back-up the .kvd/data/priv_validator_state.json file after stopping your kvd process. This file is updated every block as your validator participates in consensus rounds. It is a critical file needed to prevent double-signing, in case the upgrade fails and the previous chain needs to be restarted.
+
+In the event that the upgrade does not succeed, validators and operators must downgrade back to v0.15.2 of the Kava software and restore to their latest snapshot before restarting their nodes.
+
+## Upgrade Procedure
+
+### Before the upgrade
+
+Kava Labs has submitted a `SoftwareUpgradeProposal` that specifies block height __1803250__ as the final block height for kava-8. This height corresponds to approximately 14:00 UTC on January 19th. Once the proposal passes, the chain will shutdown automatically at the specified height and does not require manual intervention by validators. 
+
+### On the day of the upgrade
+
+**The kava chain is expected to halt at block height __1803250__, at approximately 14:00 UTC, and restart with new software at 16:00 UTC January 19th. Do not stop your node and begin the upgrade before 14:00UTC on January 19th, or you may go offline and be unable to recover until after the upgrade!**
+
+**Make sure the kvd process is stopped before proceeding and that you have backed up your validator**. Failure to backup your validator could make it impossible to restart your node if the upgrade fails.
+
+1. Export State (this **MUST** be done using **v0.15.x**)
+
+```sh
+# verify version before export: 
+kvd version --long
+# name: kava
+# server_name: kvd
+# client_name: kvcli
+# version: 0.15.0 (any 0.15 version is fine)
+# commit: 8691ac44ed0e65db7ebc4a2fe85c58c717f63c39
+# build_tags: netgo,ledger
+# go: go version go1.17.1 linux/amd64
+
+# export genesis using v0.15.x
+kvd export --for-zero-height --height 1803250 > export-genesis.json
+```
+
+**Note:** This can take a while!
+
+2. Update to kava-9
+
+```sh
+  # in the `kava` folder
+  git pull
+  git checkout v0.16.0
+  make install
+
+  # verify versions
+  kvd version --long
+  # name: kava
+  # server_name: kvd
+  # client_name: kvcli
+  # version: v0.16.0
+  # commit: [PLACEHOLDER]
+  # build_tags: netgo,ledger
+  # go: go version go1.17.1 linux/amd64
+
+
+  # Migrate genesis state
+  kvd migrate export-genesis.json > genesis.json
+
+  # Verify output of genesis migration
+  kvd validate-genesis genesis.json # should say it's valid
+  kvd assert-invariants genesis.json # should say invariants pass
+  jq -S -c -M '' genesis.json | shasum -a 256
+  # [PLACEHOLDER]
+
+  # Restart node with migrated genesis state
+  cp genesis.json ~/.kvd/config/genesis.json
+  kvd unsafe-reset-all
+
+  # Restart node -
+  # ! Be sure to remove --halt-time flag if it is set in systemd/docker
+  # NOTE: THE BINARY IS NOW NAMED KAVA
+  kava start
+```
+
+### Coordination
+
+If the kava-9 chain does not launch by January 19, 2022 at 20:00 UTC, the launch should be considered a failure and validators should refer to the [rollback](./rollback.md) instructions to restart the previous kava-8 chain. In the event of launch failure, coordination will occur in the [Kava discord](https://discord.com/invite/kQzh3Uv).