Body preview on all article lists

The article body now shows by default on all article lists. So do comment lists.

The major application of this is to quickly browser through a users's top or latest posts, e.g. ourbigbook.com/go/user/cirosantilli/articles?sort=score

Previously, the body would only show on:

Now it shows everywhere else as well, except that in other views, only a fixed height preview is shown to allow quickly going through large articles without too much scrolling.

A "view more" button can uncover the hidden content if the user wishes to usee it.

A "Show body" control was also added to toggle body vs the previously existing table mode.

Announcements: