Custom Feed issues

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• All episodes are shown bold (because there is no video component)
• Renaming the feed needs to rename the folder existing episodes are stored in
• Need to smartly prepend "http://" before URLS if the user does not.
• If a URL is wrong (or there is no network connectivity), it will add the feed but keep the dialog open, which is bad.
• Adding a feed does not update it in place. Still.

Some not limited to custom feeds but I am too lazy atm to file separate issues:

• Clearing a show does not remove downloads of those episodes