Documentation says:
These options will only be available if the "SSH support for Stash" add-on is enabled. For instructions on how to enable this add-on on your instance, please refer to Disabling and enabling add-ons.
But there is no any SSH support for Stash plugin available.
Could anybody help to activate SSH support for Git?
BTW. For Stash 3.5.1 it works without any plugin...