Adjusting text content spacing between paragraphs

[zoltanhosszu]

This PR removes spacing between paragraphs. It keeps spacing for elements following paragraphs (blockquotes, lists, attachments, etc).

[andyra]

We probably need to get some buy-in on this since the team seemed split on how to handle spacing. If we do decide we like this approach (like I do!), I think we might want to figure out some kind of content migration that inserts <p><br></p> after each paragraph, or else all previously posted content will look way too cramped.