Fixing Overflow on Long Inline Elements

[EliasPrescott]

closes #727

Here is the post mentioned in the linked issue: https://blog.rust-lang.org/2020/10/08/Rust-1.47.html

Adding overflow-wrap: break-word to the post content container ensures all child inline elements will wrap properly instead of overflowing.

I was originally going to scope the new property to .post a, but putting it directly on .post could prevent future issues instead of just fixing the tagged issue.