Plex integration defaults to first library instead of allowing selection

[jkr442]

Cliamp appears to load the first Plex library it finds, which in my case was an audiobook library rather than music. It would be great to either prompt for library selection during setup or let it be defined in the config.

[bjarneo]

Feel free to open a PR to improve the Plex implementation!

[len0rd]

hey @jkr442 i had a similar issue which i addressed with #211 by adding a new config.toml option to select libraries. if that works for you i think this can be closed