Fix links to 1.1 docs.
Actually fix the links.
Strip last if so unmatched URLs are handled.
Things have moved forever.
Restore redirect conditions.

Without them all the 1.2 links are redirected to 1.3 which is not what
we want.
Updating layout
Merge changes from pull/#439 into 1.3 docs.

* Move page contents into the sidebar.
* Moving them into the sidebar should hopefully make things simpler to
  find and use.
* Update responsive menu handling.
* Add missing translation call.
* Make sidebar text/spacing tighter. This hopefully will
  make the page nav more discoverable.
Updating navbar
Merge remote-tracking branch 'origin/1.3' into 1.3