Issue 110 : bulkOperations integration tests

Several things to review here :
* the integration tests of course
* some rewrites of the putAll and removeAll methods (with some refactorings too)
Thanks for your input in advance
Once again, a comment on maintainability, but why not factor out what you're doing here and in the other methods in to something like:

    private static Set<String> getExpectedKeys() {
      return new HashSet<String>() { {add("key1"); add("key3"); } };
    }

    private static Set<String> getNotExpectedKeys() {
      // ... similar
    }
    // in your test method:
    // put all expected + unexpected keys into cache
    myCache.removeAll(unexpectedKeys);
    // verify no unexpected keys present and all expected ones are there