[TYPO3-mvc] RFC #11229: Make the Repository unit tests green again and add repository::getObjectType

[Oliver Klee]

This is a SVN patch request.

Type: Bugfix/Cleanup

Bugtracker reference:
http://forge.typo3.org/issues/11229

Branches:
trunk

Problem:
The Repository tests fail/crash, and the Repository does not have a
public getter for the objectType (which is needed for #11230).

Solution:
Fix the tests, and add the getter.