Update use of open() in object API

* Switch to use io.open() for py3 compatibility and simpler testing.
* Open files in 'rb' mode to avoid translation on Windows

Previously tests simply relied on files that were present in the
repository to run tests using open().  Change the filenames to ensure
that no longer happens.

requests_mock doesn't have a way to match against the request body for
PUT/POST; an attempt to add a new Matcher to do that worked but it
needs to subclass the currently private adapter._Matcher class or
duplicate most of its functionality.

Change-Id: I8c30b41db20af8ecafe67e760e872fc08adec905
Close files on image create

The file opened for --file was never closed.  Close it if it is a
file object.

Change-Id: I7bd120a2413de42339771d01e8fd1894d38c3011
Close files on server create, add tests

The files opened for the --files and --user-data options were never
closed, potentially leaking memory in a long-running client. Close
them if they are file objects.

Add a couple of basic tests for server create.

Change-Id: I1658b0caa2d6af17308149cb52196ee28266ddf2
Include support for using oslo debugger in tests

Simply run `tox -e debug <test_name>` to get an interactive
debugging prompt

Change-Id: I09e5b844a33c2f0fd4230f01fbc6c0aa8d752545
Merge "Include support for using oslo debugger in tests"
Merge "Update use of open() in object API"
Merge "Change --os-auth-plugin to --os-auth-type"
Merge "Close files on server create, add tests"
Merge "Close files on image create"
Adjust some logging levels

* Promote select messages to INFO so lower logging levels can be useful
* Help more modules not say so much all the time

Change-Id: I814023c1489595998ae74efe40ef439b3522ee74
Merge branch 'examples' into dt-test
Merge branch 'low-level-api-network' into dt-test