The previous commit at [1] introduced a bug due to last
minute reordering of code, this fixes the ordering
and adds a couple of tests to verify the functionaility.

[1]: I2e3d74168976868ea1e4dd6c797f6340faa50d0f

Change-Id: Ia6f8df92b2700f63b2208290ede85f247b33bc63

edit_managed/all_tenants were moved from get_session
to the Client constructor, we should support both
for a period of time.

Change-Id: I2e3d74168976868ea1e4dd6c797f6340faa50d0f

Initializing designate client with a pre-existing keystone session
won't work as designate expects keystone session to have the
'all_tenants' and 'edit_managed' attributes:

Example code:

    keystone_session = ksc_session.Session(
      auth=keystone_auth,
      verify=True,
      cert=my_cert
    )

than later:

    self._designate_client = designate_client(
      session=keystone_session,
      region_name=region_name
    )

with that code, wrap_api_call() will raise an exception:

  AttributeError: 'Session' object has no attribute 'all_tenants'

Same goes for 'edit_managed'.

This patch moves both attributes from Keystone session to designate
Client.

Closes-Bug: 1457821
Change-Id: I13d6c9ed46406fefc8cfa5de46811e4be009f1af

Change-Id: I2e3886a66ae57e810db1b5b4cb197bc7b8c157ed

This provides bindings for:

- zones
- recordsets
- tlds
- blacklists
- limits
- nameservers

With associated unit tests.

Change-Id: Ie9b79340bd327b78916fd038633842da3ace881b

Allows users with the right role to edit managed records

Change-Id: I5502da0ca1f04e428b2723038d369d317338ce51