info: potentially useful libraries

[edilmedeiros]

Suggestions from rob in the Discord channel.

• The confy crate may be used to store common user settings like bitcoind path and the default port so they don't need to be entered every time.
• The colored crate can add some nice visual appeal to things like transactions and balances.
• The indicatif can provide some progress spinners and loading bars to expensive RPC calls, so the user doesn't see a hanging terminal.

Probably not the best place to keep this kind of note, but anyhow...

[diogocanut]

In case we need to handle more complex use cases one alternative for confy is config-rs.