No support for taxonomy meta box positioning

[jazzsequence]

Extended Taxos allows you to define a custom metabox -- which is cool -- but all metaboxes appear in the same position by default and, as far as I can tell, there's no easy way of specifying where the metabox should appear when the custom metabox is added.

A filter that allows a priority and context to be passed into the add_meta_box call would be nice. https://github.com/johnbillion/extended-cpts/blob/master/src/class-extended-taxonomy-admin.php#L338-L348