[rloth] feature on command: Perceptron() instead of pos_tag()

gargantext/util/taggers/NltkTagger.py

+#!/usr/bin/python env
 from ._Tagger import Tagger
-
-import nltk
-
+#from nltk import pos_tag
+from nltk.tag.perceptron    import PerceptronTagger
 
 class NltkTagger(Tagger):
+    '''Require maxtree'''
+    #import nltk
+    def __init__(self, *args, **kwargs):
+        self.tagr =  PerceptronTagger()
+        super(self.__class__, self).__init__(*args, **kwargs)
+
+    #~ def __start__(self):
+        #~ self.tagr =  PerceptronTagger()
 
     def tag_tokens(self, tokens, single=True):
-        return nltk.pos_tag(tokens)
+        return self.tagr.tag(tokens)