Test lemma_ with unicode input

tests/test_unicode_lemmas.py

@@ -0,0 +1,15 @@
+# encoding=utf8
+from __future__ import unicode_literals
+
+from spacy.en import English
+import pytest
+
+
+@pytest.fixture
+def tokens():
+    return English()(u'ćode codé')
+
+
+def test_unicode(tokens):
+    assert tokens[0].lemma_ == u'ćode'
+    assert tokens[1].lemma_ == u'codé'