Add operator.itemgetter support for Python <= 3.3.

Also fixes namedtuple support for these versions.

jedi/evaluate/compiled/fake/operator.pym

@@ -0,0 +1,33 @@
+# Just copied this code from Python 3.6.
+
+class itemgetter:
+    """
+    Return a callable object that fetches the given item(s) from its operand.
+    After f = itemgetter(2), the call f(r) returns r[2].
+    After g = itemgetter(2, 5, 3), the call g(r) returns (r[2], r[5], r[3])
+    """
+    __slots__ = ('_items', '_call')
+
+    def __init__(self, item, *items):
+        if not items:
+            self._items = (item,)
+            def func(obj):
+                return obj[item]
+            self._call = func
+        else:
+            self._items = items = (item,) + items
+            def func(obj):
+                return tuple(obj[i] for i in items)
+            self._call = func
+
+    def __call__(self, obj):
+        return self._call(obj)
+
+    def __repr__(self):
+        return '%s.%s(%s)' % (self.__class__.__module__,
+                              self.__class__.__name__,
+                              ', '.join(map(repr, self._items)))
+
+    def __reduce__(self):
+        return self.__class__, self._items
+