public function testGet()
 {
     $lVar = PersistentVariableTable::get('affen');
     $this->assertTrue(is_object($lVar));
     $this->assertEquals(hugo, $lVar->getUsername());
     // 2nd run shall fail due not existing key
     $lVarFailed = PersistentVariableTable::get('dasgehtschief');
     $this->assertTrue(is_null($lVarFailed));
 }