Genesis port script for 0.34

[cwgoes]

Write a script, in Golang, using the old genesis type and new genesis type, to convert an export from the current Cosmos Hub mainnet to the correct import format for 0.34 after the transfers-enablement hard fork.

Note the parameter changes per this proposal draft, which I think are accurate.

Ref #3880

Should result in an actual executable, which can be run as such:

gaiad export | genesis-port [chain-id] [start-time] > new_genesis.json

cc @jackzampolin @rigelrozanski Anything I missed?

[alexanderbez]

Looks reasonable to me.

[fedekunze]

the genesis file gets printed to stdout via fmt.Println. Imo that's a huge amount of lines. Would it be better to write the export genesis into a JSON which can be used as a path for the port command ?

[alexanderbez]

I see no harm in printing to STDOUT -- it's what export does. Optionally, your script can take a flag --output/-o [file] which writes it to file instead of STDOUT.