Views Plugin Argument Default Referer

Adds a views plugin argument default that retrieves a Node ID from HTTP_REFERER.

This plugin was created as a reaction to the following issue on the Media module https://www.drupal.org/node/2260543.

I was pointed to the fact that this module is a duplicate of module https://www.drupal.org/project/views_contextual_filter_query.
As a matter of fact that module offers more functionality by providing an option to the user which parameter should be used.

Changing the project's development status to obsolete.