Display Relay Icons in Relays View [Feature Request][UX]

[alltheseas]

User Story

As an advanced Damus user who wants to tinker with Relay settings, I would like to visually recognize relays on the relay settings page, so that I can more intuitively manage my relay settings.

Acceptance Criteria

1. Damus automagically pulls icons associated with each relay
2. Damus displays relay icon on each relay row in relay settings view

Mockup:

Reference
See https://github.com/nostr-protocol/nostr/issues/128.

Why not get the favicon from the domain, similar to NIP-11?
E.g. wss://relay.damus.io/ -> https://relay.damus.io/favicon.ico

Relay sets feature request#453

[alltheseas]

@robagreda @bryanmontz @BenGWeeks