Implement a protocol handler/meta data provider

[andrew-codechimp]

Currently the URL's are hard coded with usernames/profile/server details. When these are favourited they will be static and if the config changes will not update, they also leak credentials.

Register a protocol handler for tvh:// content and re-write URL's on the fly.
Ditto for icon sources.

See https://github.com/pierrepoulpe/SqueezeboxQobuz for a fairly simple implementation.