Hide the empty sidebad TOC on the search page

This uses @dnephin's changes to the base.html (thank you!)

and then adds the hide_toc: page meta

Docker-DCO-1.1-Signed-off-by: Sven Dowideit <SvenDowideit@docker.com> (github: SvenDowideit)
Merge pull request #8528 from SvenDowideit/hide-side-toc-for-search

Hide the empty sidebar TOC on the search page