Alternatives to key pair file for signing

[ruuda]

At the moment, the solido CLI does not integrate with any software or hardware wallet; it reads a key pair from ~/.config/solana/id.json (or an alternative file if desired) and it uses that to sign. The associated account pays for the transaction fees and making accounts rent-exempt.

When we are going to set up the multisig, I suppose that we don’t want to use a key pair stored in a file. @malikankit , @mkaczanowski, do you know what we will use instead? The Solana CLI does support hardware wallets, so I think it should be possible to support this in solido as well.

[enriquefynn]

We should definitely add support hardware wallets

[malikankit]

Yes, we should at the least support Ledger.

cc : @Reisen : any useful pointers for this?

[enriquefynn]

Closed by #154