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
Thanks to @metajack!