Allow keystoneclient to work with older keystone installs

Older keystone installs may return 501 for GET / instead of 300
like today. We should be able to assume that if 501 is returned the
server will support v2.0 only.

Fixes bug 1159911

Change-Id: If264840d8678a490264f1bdb62f1b51c362619e1
Add find() method to CrudManager

Add a find() methods to CrudManager to maintain compatability
with existing CLI lookups using utils.find_resource().

Change-Id: Ia9b38b975bb88fb361f3471b66f98c7e81bbc6de
Fix --version to output version

Change-Id: I7d8dc83ac7c2ad7519633d136c1c32ce8537dce8
Fixes: bug 1182675
Fix line continuations (flake8 E125, E126)

- E125: continuation line does not distinguish itself from next logical
  line
- E126: continuation line over-indented for hanging indent

Change-Id: I626a6d5d57db927e8b239f90569b5601c772f28b
Fix unused imports(flake8 F401, F999)

- F401: imported but unused
- F999: syntax error in doctest

Fixing a couple of the F401's simply required fixing the doctests syntax
where the imports were actually in use.

Change-Id: If78abbb143daf8d005a71c5ab52836df29c5e0cd
Merge "Fix line continuations (flake8 E125, E126)"
Merge "Fix --version to output version"
Merge "Fix unused imports(flake8 F401, F999)"
Merge "Add find() method to CrudManager"
Merge "Allow keystoneclient to work with older keystone installs"