xucli unlock enhancements

[kilrau]

After #1090 is done, a crashing lnd or raiden (xud stays running) should be unlocked automatically by securely preserving the pw in-memory.

[sangaman]

I have verified that this should actually already be working, it works for me in local tests. Can you try this in one of your environments? Simply bring down lnd and then bring it back up and see if it unlocks automatically.

[kilrau]

Not for me (xud-docker mainnet):

mainnet > status2
┌───────────┬──────────────────────────────────────────┐
│ SERVICE   │ STATUS                                   │
├───────────┼──────────────────────────────────────────┤
│ bitcoind  │ Ready                                    │
├───────────┼──────────────────────────────────────────┤
│ lndbtc    │ Ready                                    │
└───────────┴──────────────────────────────────────────┘
mainnet > restart lndbtc
Restarting mainnet_lndbtc_1 ... done
mainnet > status2
┌───────────┬──────────────────────────────────────────┐
│ SERVICE   │ STATUS                                   │
├───────────┼──────────────────────────────────────────┤
│ bitcoind  │ Ready                                    │
├───────────┼──────────────────────────────────────────┤
│ lndbtc    │ Wallet locked. Unlock with xucli unlock. │
└───────────┴──────────────────────────────────────────┘

[sangaman]

OK thanks, I will have to debug to see why it's not working on docker.

[kilrau]

Working fine for me now. Closing.