Implement left navigation table of contents for documentation
Implement left navigation table of contents for documentation

Changing the TOC for the documentation to use a floating left navigation
instead of at the top of the page. This will improve content
discoverability and readability.

Change-Id: Ibbdaddbdc2e18a3fe35c126f4074cd9e079449ee

gerrit-review/gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,WANdisco/gerrit,gerrit-review/gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,gerrit-review/gerrit,qtproject/qtqa-gerrit,qtproject/qtqa-gerrit,gerrit-review/gerrit,WANdisco/gerrit,gerrit-review/gerrit,WANdisco/gerrit,qtproject/qtqa-gerrit,qtproject/qtqa-gerrit,GerritCodeReview/gerrit,GerritCodeReview/gerrit,qtproject/qtqa-gerrit,WANdisco/gerrit,WANdisco/gerrit,GerritCodeReview/gerrit,WANdisco/gerrit,gerrit-review/gerrit,WANdisco/gerrit