First pass at refactoring Salt documentation.
Merge conflict and rebase.

Conflicts:
	doc/ref/renderers/index.rst
Wrapping up sub-TOCs.
Moving around Windows docs.
Now compiling cleanly except for GCE.
Fix GCE build errors.
Fix line length
Docs build cleanly! Yay!
Remove spurious heading. Thanks @gravyboat!
Merge pull request #10792 from cachedout/doc_toc

Documentation overhaul