Default rename to existing
Don't render the <audio> tags when not needed

A user reported on mobile safari seeing issues with unplayable audio
blocks.
Correct page logic

fixes #82
Backoff new updaters to 3 hours

The current system is working great. In lieu of something that figures out
if an update task is already running, just start them in longer intervals.
This should prevent a bunch from running concurrently.
Show shortcuts dialog on ? click
Direct todo list to github
Error on template render
Stripe subscriptions
Remove unused
Move button working text to after checkout click

The stripe dialog has no event or callback on close. This caused the button
to be stuck in the loading mode.
Better sub reasons
Add upgrade ad beneath feed list
Don't show upgrade blurb without stripe
Remove some error prints
More error print removal
Mark as read if the title is fully on the screen

fixes #90
Scroll to top on feed/folder change
Correctly set feed folders after move
Explicitly say that deploying requires the dev setup

fixes #131