public function testAppendValue2()
 {
     $c = new Configuration(array('foo' => array('bar' => true)));
     $this->assertNull($c->getValue('foo/blah'));
     $c->appendValue('foo/blah', 'one');
     $this->assertEquals(array('one'), $c->getValue('foo/blah'));
     $c->appendValue('foo/blah', 'two');
     $this->assertEquals(array('one', 'two'), $c->getValue('foo/blah'));
     $c->appendValue('foo/blah', 'two');
     $this->assertEquals(array('one', 'two', 'two'), $c->getValue('foo/blah'));
 }