Adding initial barbican client and model

Creating a barebones structure for barbican tests.

Change-Id: I57966ffd3d250e5bea13648cc0d8164a404473cc
add glance models
Add a conftest and unittest.json.config to run unittests. Should close #2.
Merge "Adding initial barbican client and model"
[#1] add unit tests for (Glance) Image model.
Merge branch 'master' into glance. @kaofelix added improved pytest folder structure.
[#1] move pytest into new folder structure
[#1] add `test_image_string_representation` test
Modifications for alternate behavior for deleted images

* Added logic to image behaviors to handle GET requests for
  deleted images returning the image or a 404
* Added config option to specify behavior for deleted images

Change-Id: I42c07af2a935a66000be964c055e0616752d8ac6
Merge "Modifications for alternate behavior for deleted images"
Adding behaviors for meniscus tenant api

Adding equality customization.

Change-Id: I0fe935d5ee4ded37706191ceeab28c7c3d782490
Merge "Adding behaviors for meniscus tenant api"
Attributes for create backup action

An attribute to create backup in server client.
An attribute to create active backup in Image behavior.
Create Backup request class.

Change-Id: I5d3e21c0e3a1a335ece13f01dbd7c1392c5d8a54
Merge remote-tracking branch 'upstream/master'
Start of removal of model tag vars

* Removed tag/root tag vars from models except where still needed
  for auto serialization

Change-Id: I261bfd4bfa9cd6e9c0b8fb3eba3a3ef39f2aab00
Updated reference config

* Updated devstack and reference configs to match latest config params

Change-Id: I5ada3e7541c398156a69565499319c762c6ab4c1
Merge branch 'master' into glance
Code review
Merge "Updated reference config"
Merge "Start of removal of model tag vars"