feat: add instructions for testing migration file hash (#1143)

* feat: add instructions for testing migration file hash

* fix: sort json before hashing

migrate/v0_16/testing_genesis_hash.md

@@ -0,0 +1,21 @@
+### Testing kava-9 migration
+To verify that the migration procedure for kava-9 is deterministic, run the following commands to compute the genesis hash of a known block.
+
+```sh
+# install latest v0.16 release candidate
+cd $HOME/kava  # replace if location of kava directory is different
+git fetch
+git checkout v0.16.0-rc3
+make install
+cd $HOME
+
+# download block 1627000 from kava-8
+wget https://kava-genesis-files.s3.amazonaws.com/kava-8/block-export-1627000.json
+
+# run the migration (make sure there are no other kava processes running)
+kava migrate block-export-1627000.json > block-export-1627000-migrated.json
+
+# calculate hash of migrated file
+jq -S -c -M '' block-export-1627000-migrated.json | shasum -a 256
+```
+