Create a new base REST API interface

* restapi module provides basic REST API support
  * uses dicts rather than Resource classes
  * JSON serialization/deserialization
  * log requests in 'curl' format
  * basic API boilerplate for create/delete/list/set/show verbs
* ignore H302 due to urllib import

Change-Id: I3cb91e44e631ee19e9f5dea19b6bac5d599d19ce
Object API commands using our REST API layer

* Add object-store API to ClientManager
* Add object-store client
* Add Object API library in openstackclient.object.v1.lib
* Add Object API {container,object} list commands
* Add library tests
* Add command tests

Change-Id: Ib1770d45efa8871959826b85faafa1e0bcef0a03