Link CiviCRM entity types to CMS content types

This improvement is being commissioned by Tadpole.
This project is currently for WordPress, although we should leave the door open for other CMS integrations to plug into it:

• Allow you to specify one or more Civi entities and associate them with a WP post type
• Give you some filters (only events of type X, or only surveys of campaign Y)
• Automatically create a post containing the appropriate shortcode when a new entity matching the filters is created.
• Link Civi tags with WP tags, and Civi Campaigns to WP categories