add_rewrite_tag error on register_taxonomy

On my local install I'm getting an issue:

`Fatal error: Call to a member function add_rewrite_tag() on a non-object in /Sites/wptt-development/wp-includes/rewrite.php on line 51`

Looking through other docs on registering taxonomies it seems that it should be registered on the 'init' hook. WP_Logging is loading on 'plugins_loaded' which looks like is set before our taxonomy objects are set (hence the error).

Changing to 'init' fixes the error.

Changing register_post_type to init brings it in to line with register_taxonomy