Mix multiple RSS feeds locally

[BinToss]

TODO

• [ ] Add a list to store and configure RSS feeds for checking new releases. See Note 1.
• [ ] Add a list to store and configure RSS feed for searching for releases by title. See Note 1.
• [ ] Allow selecting multiple RSS feeds via checkboxes so their contents can be combined and displayed in the Torrents panel.
• [ ] De-duplicate results from combined RSS feeds.
• Note 1: Until feeds can be combined, radio buttons should be used instead of checkboxes, so the user can select a preferred RSS feed similar to the current implementation (URI text box and drop-down list).

Granted, one could simply use a service such as RSS Mix, Feed Combiner, RSS Mixer, or RSS Combiner. However, that means one's RSS feeds could become unavailable if the service they chose is slow or not responding.