generics in unit tests

git-svn-id: https://svn.apache.org/repos/asf/cayenne/main/trunk@1507809 13f79535-47bb-0310-9956-ffa450edef68
unused import

git-svn-id: https://svn.apache.org/repos/asf/cayenne/main/trunk@1507810 13f79535-47bb-0310-9956-ffa450edef68
Java 1.6 @Override for interface methods

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