avoiding name collisions when looking for md5 in fragment

--HG--
branch : distribute
extra : rebase_source : 8b9469b9b9b4d8769ee5e6655aa1b75c207905b8

pkg_resources.py

@@ -2049,7 +2049,7 @@ def _remove_md5_fragment(location):
     if not location:
         return ''
     parsed = urlparse(location)
-    if 'md5' in parsed[-1]:
+    if parsed[-1].startswith('md5='):
         return urlunparse(parsed[:-1] + ('',))
     return location