Continued byline changes

[benlk]

Changes

• Creates new conditional function largo_post_was_updated( $post ) in inc/conditionals.php
• Uses largo_post_was_updated in Largo_Byline and its inheritor classes to determine whether to show the published date or the updated date
• Updated date is only show if the post was updated and if the byline is being displayed in the context is_single()
• The updated date now uses a <time> element, to match the published date
• Removes the h5.top-time time element from the single post template, and styles for it
• Removes styles hiding the date in the single-post and single-page bylines

Why

For #1259, continuing #1126.

For the Rivard Report.

[aschweigert]

so is the behavior here that we show either the updated date OR the published date but not both? are we still doing the XX hours ago for posts published/updated in the last 24 hours? or just posts published in the past 24 hours?

[benlk]

Here's what shows:

	published within 24 h	published more than 24h ago
Updated	Shows updated date	Shows updated date
Not updated	Shows the largo_time "XX hour ago" format	Shows the published date

[benlk]

let’s make the updated date also do the XX hrs ago thing
and then that’s fine to merge i think
some sites may want to show published and updated
but this should be the default

• updated date in the XX Hours Ago format, as new function largo_time_updated

[aschweigert]

lgtm, passing this to @rclations for a second set of eyes and then let's merge

[rclations]

everything looks good to me!

[benlk]

And the failing tests are the usual, so I'll merge this and deploy it to Rivard.