v1.1.0 - New categories

Added

• Support for the new Apple Podcast categories that were added August 9th 2019.
• Documentation of the Warning classes defined by PodGen.

Changed

• Using one of the old iTunes (sub)categories will now generate a LegacyCategoryWarning.

Deprecated

• Importing NotSupportedByItunesWarning from podgen.not_supported_by_itunes_warning. Import from podgen instead.