Reorder index links

The V3 Client link should come before the V2 Client link if that's
what we want developers to use.

Change-Id: I34a232d21862999a6f1a7acf5382ff752a7e3590
Cleanup docs - raises class

The argument to the :raises: directive is the class name. If the
class name is a valid reference it's rendered as a link to the
class. This change cleans up the :raises: directives to use the
reference correctly and use a valid class reference.

Change-Id: I84188b60de0ab4c6b5b2fb5a203c43bfde094707
Merge "Cleanup docs - raises class"
Merge "Reorder index links"