Rename fixtures directory to job_fixtures to prepare for adding view_fixtures
directory in the following commits.
Change-Id: Ic20997cae020b542ddc22bf444fa6b92fbcae064
Implement custom tags for including files by subclassing YAMLObject to
allow PyYAML to easily convert from the Yaml nodes.
Change to support both lists and strings under the same tag name and
deprecate the old tag naming. Rename tests using the deprecated tags to
ensure they are not used for examples. Remove old tests that simply
duplicate others.
Change-Id: I1a8d3376ea6e4918a2adb05fb856b939a3124d74