Add Need-YouTube-Link UI for managing episodes without YouTube links

-Note another change to settings.py.skel

-Added method for me to easily determine which episodes in the system
still need YouTube links (ones that are for a podcast with
"managed_by_superuser=True" and have no youtube_rss), and to navigate to
its episode_update page. This superuser UI could be made nicer if it had
an input for each episode's youtube_url right next to the title, and I
could make the changes directly from the page without refreshing the
page, but that'd require some kinda Ajaxing, I'm not sure how to
implement it, and I can move about as quickly through the episodes by
opening each episode_update page in a New Tab.
Delete unnecessary __init__ function

Not needed, shouldn't have pushed this.