#653628 by dagmar and dereine: Ensure child method declarations match parent method declarations to prevent notices.

o #482162 by agentrickard: link path needed further sanitization to properly encode special characters.

Major re-organization of handlers. PLEASE NOTE: This drastically affected the Views module API and until modules are updated to match, they will stop working. Efforts have been made to ensure that this won't cause your site to crash, but that's partly up to the individual module as well.