- Added chunk_node argument to ChunkScore constructor -- tells it what   chunks to pay attention to. - Removed unused (obsolete) method ChunkScore._chunk_toks()
- Added chunk_node argument to ChunkScore constructor -- tells it what
  chunks to pay attention to.
- Removed unused (obsolete) method ChunkScore._chunk_toks()


svn/trunk@6151

nltk/nltk,nltk/nltk,nltk/nltk