Implement local bookmark(hashtag #) for Acid2

To test this, execute the followings:
    test_local_bookmark.html#text1
    test_local_bookmark.html#text2
    test_local_bookmark.html#text3
    test_local_bookmark.html#top
    test_local_bookmark.html#h3
    test_local_bookmark.html#num
    acid2.html#top
     - The link from acid2.html works now. ( `<a href="#top">`)

Thanks to @metajack!