This updates the Initial Status Updates and Change entries to factor in

the timestamp and state of any status updates when determining whether

an entry should be collapsed.
Both types of entries will be uncollapsed if there are any pending

status updates. These updates are triggering periodic checks, and their

entries might update while the user is viewing the page. We don't want

to risk hiding the content by default by collapsing their boxes.
They also both now factor in the user's last visited time. If the user

has visited the page before, and the status update has been updated

since that last visit, the entry won't be collapsed.
The Initial Status Updates entry used to default to always stay expanded

if there weren't any Change entries yet on the page. Now this only

happens if the user has not visited the page before, ensuring that it's

always shown by default for new visitors and for anonymous users, but

that users who have already viewed the page will see it collapsed unless

there's actual new content to show.

Unit tests pass.