QGOV changes, #4

[ThrawnCA]

Overview

Changes to become more compatible with qld-gov-au fork, see #4. This includes several feature improvements.

• Capture Flake8 config in a .flake8 file so it applies to manual runs.
• Use ckan_cli script so we can run Click or Paster with the same syntax.
• Fix typos in README.
• Add more documentation of CLI commands.
• Add check to ensure that package and resource IDs in URLs match up.
• Increase use of six for Py2/Py3 compatibility.
• Add a title to validation report links (just containing the validation timestamp).
• Use a helper to more robustly detect CKAN 2.9+ in templates, so we're ready for CKAN 3.
• Encapsulate database access in ValidationStatusHelper so job logic is simpler.
• Turn custom actions into chained actions so other plugins can customise them further.
• Update job enqueueing so we only record a resource ID, not the full dictionary (saving memory in Redis).
• Skip job enqueueing if we already have a job in progress.
• Don't trigger a new validation job for package_patch calls that don't change any resources.
• Move the main plugin module up a level, to plugin.py, to simplify paths.
• Don't validate "sibling" resources when a single resource is updated.
• Use parameterised logging instead of up-front formatting.
• Mark broken tests to be skipped, instead of commenting them out.
• Use io.BytesIO instead of six.BytesIO for fake files, since it's more consistent.
• Pin ckanext-scheming version for consistent testing.