v2.4.0

Enhancements:

• Added new search arg for the [ucf-news-feed] shortcode, which allows you to filter results by a search query.
• Tidied up UCF_News_Feed::get_news_items() and adjusted UCF_News_Feed::format_tax_arg() a bit to omit unset/empty query args from the final feed URL that's requested, and support custom feed URLs that already include query args.
• Upgraded packages