MBTextWrapper: drop dedicated __init__ method

MBTextWrapper: drop dedicated __init__ method

It was only there as a compatibility layer with a version of Python which we do
support anymore.

--- a/mercurial/util.py	Mon May 18 16:54:21 2015 -0500
+++ b/mercurial/util.py	Mon May 18 16:56:04 2015 -0500
@@ -1554,13 +1554,6 @@
 
         This requires use decision to determine width of such characters.
         """
-        def __init__(self, **kwargs):
-            textwrap.TextWrapper.__init__(self, **kwargs)
-
-            # for compatibility between 2.4 and 2.6
-            if getattr(self, 'drop_whitespace', None) is None:
-                self.drop_whitespace = kwargs.get('drop_whitespace', True)
-
         def _cutdown(self, ucstr, space_left):
             l = 0
             colwidth = encoding.ucolwidth