add a setup method to listeners

For use when a listener should do something always whenever in a request
it is loaded
Make mapResources test more flexible

Unfortunately, the number of controllers in the core's test_app folder
changes with different versions. Rather than create a copy of the
controller, or by messing around with the cache class to "mock"
controller objects - make the test able to cope with any number of
controllers. Even though this goes against the idea of always having
static expectations for robustness.
"Fix" translations test also

if the (new) TestConfigs controller is missing - remove it from
expectations
test that setup is called on load
Merge pull request #84 from jippi/feature/listener-on-load

RFC: add an onload method to listeners