Fix consoleauth check_token for rpcapi v2

In 48dd52095869d36970de232f5dfa60656fcd578b support for the 2.0
consoleauth rpc API was added which missed the return statement in the
check_token method. Because of this all the components that had to
verify a token against consoleauth component would fail to do so.

This patch fixes the check_token method and extends the tests to cover
the new v2.0 class.

Closes-Bug: #1244220
Change-Id: I4e5186943d28609083f723f4b43ab6f0ecbffd27