Add more friendly settings to wp-admin page

[Tom Harrigan]

Settings screen should allow configuration options such as (but not limited to):
-selecting which public post types are made available for consumption via the news functionality
-selecting which category (or other taxonomy) terms are made available for consumption via news functionality

Utterances, intents, slot types should be updated appropriately. Ex.:
-Alexa, ask skill_name for Technology (tax_term) content
-Alexa, ask skill_name for Gallery (post_type) content