Since methods defined in the controller helper are mostly delegated to
the controller, delegate respond_to? as well, so that for example
`respond_to?(:params)` behaves as expected.
A few have been left for aesthetic reasons, but have made a pass
and removed most of them.
Note that if the method `foo` returns an array, `foo << 1`
is a regular push, nothing to do with assignments, so
no self required.
