revert 29c9e1 for python3 work

src/cdiff.py

 
 import os
 import re
-import errno
 import difflib
 
 
         # args stolen fron git source: github.com/git/git/blob/master/pager.c
         pager = subprocess.Popen(['less', '-FRSXK'],
                 stdin=subprocess.PIPE, stdout=sys.stdout)
-        try:
-            for line in color_diff:
-                pager.stdin.write(line)
-        except IOError as e:
-            if e.errno == errno.EPIPE:
-                pass
+        for line in color_diff:
+            pager.stdin.write(line)
 
         pager.stdin.close()
         pager.wait()