Allow `--unlock` functionality when ganache is already running

• I asked about this on gitter: [x]
• Link to my question on gitter: https://gitter.im/ConsenSys/truffle?at=5ea068f0f39e5c2fbb970216

Summary

It is possible to unlock accounts with the --unlock flag when launching ganache. It would be useful to be able to do this while ganache is already running.

Context

When combined with--fork, --unlock is very powerful in that it lets the me simulate mainnet transactions from accounts I don’t control. However, I like to play around in the console and so often don’t know which accounts I want to unlock ahead of time. Currently each new unlock means exiting, restarting, and repeating a (sometimes lengthy) series of transactions.

Possible Solution

I have three ideas for possible implementations:

1. Add a cli flag --unlock-all that arbitrarily allows transactions to be broadcast from any address, without having to explicitly unlock first. In my mind this is the best approach.
2. Add a new custom RPC endpoint that accepts an address as a single parameter, and unlocks that address.
3. Modify the behavior of personal_unlockAccount so that any account may be unlocked with a passphrase of null. Optionally add a cli flag that enables this behavior.

[surajsjain]

Is there any way I can use this with the latest version (or a different branch) of Ganache CI so that I can unlock all the accounts?

[iamdefinitelyahuman]

Implemented in #622