Make Site Branding block event relative

Problem/Motivation

Regardless of where on the site a user is, the branding block always shows the site name and links to the top level home page. Ideally when viewing anything related to a specific event, it would show the name of the event and link to the event detail page.

Proposed resolution

Fork the Site branding block provided by core and add logic to be entity relative, similar to Smart Menu Links or the custom CTA block.