Added full support for picking templates on entities, including nodes, users, taxonomy-terms, comments, and custom entities.

Issue #2005402 by Dave Reid: Abstracts template finding function to work for all entity and bundle types. Also adds a hook for other modules to alter the list of templates suggested.

Issue #2008016 by Dave Reid: stores the template information in the node object, which prevents unnecessary database calls.

Cleaned up formatting to adhere to Drupal coding standards. Fleshed out README.txt. Prepared everything for an alpha release.

Replaced content type configuration with granular permissions. Cleaned up code comments and removed debugging information.

First working draft. Added database functionality for storing template choices. Node templates are detected and used based on a naming convention.