Implemented XF Quick Search: Search Sportsbook Events Only

NOTE: This was a [PAID] request that has been graciously donated back to the community for inclusion in core.

As per title, the option to search Events only via xf quick search (default CHECKED).

All Sportsbook pages now are default checked to search Events Only via the Quick Search.



NOTE: Category and Event pages are default checked to search within the Category Only (includes subcats). Users can uncheck the "Search this category only" and still contain the search within Sportsbook. Unchecking "Search Events only" disables both Sportsbook options allowing a Global search.