Replace Unidecode package with text_unidecode package #1014 (#1060)

Closes #1014

Author: artofhuman

graphene_django/utils/str_converters.py

@@ -1,5 +1,5 @@
 import re
-from unidecode import unidecode
+from text_unidecode import unidecode
 
 
 def to_const(string):

setup.py

@@ -66,7 +66,7 @@
         "Django>=1.11",
         "singledispatch>=3.4.0.3",
         "promise>=2.1",
-        "unidecode>=1.1.1,<2",
+        "text-unidecode",
     ],
     setup_requires=["pytest-runner"],
     tests_require=tests_require,