Prettify the published at rather than created at

This is relevant when I have a post that has been a draft for a long
time, then it would previously show the date of when the post was
created initially on the page.
Verify that records are saved after observers have been notified

This behavior was not tested previously.

I had some problems testing this because it seemed like `record.save`
was being called multiple times from somewhere else so when I expected
that #save should have been called once it had been called twice. Not
sure why this was happening.
Specify the type of what to search for

This fixes a violation "Dependency inversion principle"
Remove todo marker that I don't see how to remove