Feature: Provide ability for users to filter feed enclosures based on MIME content type and/or file extension


Some podcast feeds provide syndicated content in multiple formats. This can be the same content encoded in multiple formats (e.g. an audio show offered in MP3 and WMA formats) or a single feed entry with multiple content in possibly multiple formats (e.g. a podcast that offers both an audio and video version of episodes, in multiple formats).
It would be a useful if users could either filter feed content based on MIME content type and/or file extension, with possibly providing a means of downloading content to different physical directories based on the content format.
  1. After adding a feed, users can indicate that they only want to download audio content.
    1.1. If user indicates they only interested in audio content, they are provided with the option to only retrieve audio content that matches a specific format (MP3, WMA, etc.)
    1.2. User can specify the physical path to save feed content to based on the content format. e.g. C:\Doppler\MyFeed\audio\mp3, C:\Doppler\MyFeed\audio\wma, etc.