Addition of a vertical scroll bar as a result of rtd-footer-container on none RTD hosted sites

[andrewcoughtrie]

When hosting on a none RTD site (specifically on GitHub pages in this case) the addition of the rtd-footer-container results in a scroll bar on the primary sidebar even when the length of the list is significantly shorter than the page. Modifying the html of the page and removing the rtd-footer-container fixes this behavior.

[drammock]

thanks for reporting. I think that div is supposed to be suppressed if it's empty, so the fact that it still shows up is definitely something we should fix. (or if we're not trying to suppress it, then we should be!)