Handle NOT NXQL constraint such as dc:contributors/* <> 'pete' for MongoDB

Currently the MongoDB repository doesn't handle NOT semantic on list element such as it's explained here.

During this development, please add this test in TestSQLRepositoryQuery#testQueryNegativeMultiple:

dml = session.query("SELECT * FROM Document WHERE dc:contributors/* <> 'pete'");
assertEquals(2, dml.size());