[Feature Request] Support Podcasts

I would like to see Funkwhale support audio podcasts. As these are just audio files, storage would be the same as storing music. A podcast would only differ from a music track in the metadata fields it has attached. Files could be stored with a flag indicating if they are a music track or podcast episode and this flag would determine what labels are shown on fields in the UI. Album would be Podcast/Show, Artist would be Host(s), Track would be Episode, etc. The listening experience wouldn't need any customization, though forward/backwards skips and playback speed would be nice additions.