Remove unused imports

cdiff.py

@@ -25,7 +25,6 @@ if sys.hexversion < 0x02050000:
     raise SystemExit("*** Requires python >= 2.5.0")
 IS_PY3 = sys.hexversion >= 0x03000000
 
-import os
 import re
 import subprocess
 import errno

setup.py

@@ -3,7 +3,6 @@
 
 from __future__ import with_statement
 from distutils.core import setup
-import os
 from cdiff import META_INFO as _meta
 
 import sys