     /**
      Register an instance.
      
-     - returns: The unique `Key` for this registration.
+     - returns: The unique `Key<T>` for this registration.
      
      - parameters:
         - instance: The instance to register.

     - returns: The resolved dependency or `nil` if it is not found.
     
     - parameters:
         - container: The key to resolve.
         - parameter: A parameter to pass to the resolution block.
         - cached: Whether to use the cached value or to call the block again.
     

    /**
     Register an instance.
     
     - returns: The unique `Key<T>` for this registration.
     
     - parameters:
         - instance: The instance to register.
