Support v3 private keys

[conorsch]

The role can generate v3 Onion URLs, but doesn't currently support provisioning them from vars (which has long been supported for v2). Since the v3 URLs are a different format, we'll need to handle slightly differently, but that's fine given the optional v3 flag in the vars dict.

The v3 keys are binary files, so the sanest method to support storing in vars is to base64encode the value prior to storing. The role would then automatically base64decode the var value when writing to the v3 key file.

Thoughts? Happy to submit a PR.

[t2d]

You are right. This is overdue. Looking forward to your PR.

[xshadow]

The role supports provisioning support from the vars file via v3 flag:

  #
  # nextgeneration hiddenservice only available in tor >= 0.3.2.1
  # https://trac.torproject.org/projects/tor/wiki/doc/NextGenOnions#Howtosetupyourownprop224service
  #
  nextgenhiddenservice:
     hidden_service_hostname:
     hidden_service_version: 3
     hidden_service_ports:
        - [25, 25] 
        - [587,587]
     hidden_service_private_key:

I like the idea of base64 en/decoding, that would be a lot easier.