title: NE tags in NLTK ConllCorpusReader
body: <p>I'm trying to use CoNLLCorpusReader for CoNLL2003 dataset. This dataset contains 4 columns (example):</p>
  
  <pre class="lang-html prettyprint-override"><code>WORD      POS   CHUNK NE
  U.N.      NNP   I-NP  I-ORG
  official  NN    I-NP  O
  Ekeus     NNP   I-NP  I-PER
  heads     VBZ   I-VP  O
  for       IN    I-PP  O
  Baghdad   NNP   I-NP  I-LOC
  .         .     O     O
  </code></pre>
  
  
  
  <p>I create corpus and it works - I can get words, sents and tuples with pos tags and chunk tags.</p>
  
  <p>The question is, how can i get Named Entity tags from my corpus? I know there is corpus.raw() method, but is there really no way to get it with something like corpus.iob_words()? I found this issue: <a href="https://github.com/nltk/nltk/issues/63" rel="nofollow noreferrer">https://github.com/nltk/nltk/issues/63</a>, but in the latest version of this corpusReader there are no additional arguments in iob_words method that I can use to change the list of columns I want to get.</p>