The Elasticsearch tests now depend on an environment variable being set so we can safely install elasticsearch-py without Wagtail automatically assuming Elasticsearch is installed and running the tests.
This makes developer setup slightly easier, but also opens up the possibility for running some of the ES tests that don't depend on a running ES instance.
The `wagtailsettings` module is useful enough that it should be included
in the Wagtail contrib section, to make it available to all Wagtail
developers.
All the code has been given a once-over to make sure it is nice and
polished before being copied in. As such, this is not a direct copy of
the `wagtailsettings` module. It should be backwards compatible though,
excepting the new location.
It has been moved to `wagtail.contrib.settings`, following the naming
scheme set out in #1504.
Documentation has been concatenated in to a single page, and added to
the contrib reference section.
All `.. code::` instances have been changed to use `.. code-block::`,
and have been properly formatted. The syntax names have been normalised,
so all django templates use the `html+django` syntax, shell commands use
`sh`, and plain text uses `text`.
* State the requirement for Node.js up-front (since it's required by everyone, not just front-end devs)
* Point to vagrant-wagtail-develop instead of making people set up a Vagrant instance manually
* No need to fiddle with python paths via local.py - 'setup.py develop' handles that
* Skip instructions for virtualenvs (anyone who decides against the Vagrant route is expected to know how to use them)
