Makes versions API output deterministic

Makes the order of available versions that the API version
information is returned to clients deterministic. This is
necessary to ensure that with PYTHONHASHSEED to fixed to 0 the
unittests will consistently pass.

Change-Id: I5b7f6b7f061424adc2263c485562e72c7cc29255
Partial-Bug: #1350287
Merge "Makes versions API output deterministic"