Improve support page design

We should address @DerekNonGeneric's feedback: yet to be mentioned is that this page is missing a few items:

Breadcrumbs
Title
Sidebar
Container
The reason for this is because it uses the very bland meta.j2 template.

https://github.com/ampproject/amp.dev/issues/2339#issuecomment-535322115

Start by locating the support page and the meta.j2 template mentioned in the issue, then compare the page with other site pages that include the missing elements. Done means the support page has breadcrumbs, a title, a sidebar, and a container instead of the bland meta.j2 presentation.

Written by the indexing model from the issue text.