Return gracefully on feed URL not being found (404)
Modulized audio link parsing and included alternative feed layout
Continue gracefully on audio URL not being found (any HTTP error thrown by urllib)
Removed debug output
Cleanup
Proper handling of episode entries returning empty urls
If no audio urls have been found: suggest that the MIME type is unknown and the display the existing types of the current feed
Added support for MIME audio/x-m4a