Overview
Return less data on the Posts page, but let users easily load more.
Background
Users with a lot of posts won't want to see a ton of them immediately. We should keep the page small and limit the backend load by returning a smaller set of data.
Implementation
Show 25 posts per page. Automatically load more posts as user scrolls to bottom of the page. See T339: Show blog posts on posts page for more info.
Design
Should show a loading indicator when user reaches bottom, but data hasn't loaded yet.