close sockets on httprepository deletion (issue1487)

With this destructor in place, I no longer see tracebacks
on the server after using win32 clients for pull, push, etc.

mercurial/httprepo.py

@@ -38,6 +38,12 b' class httprepository(repo.repository):'
 
         self.urlopener = url.opener(ui, authinfo)
 
+    def __del__(self):
+        for h in self.urlopener.handlers:
+            h.close()
+            if hasattr(h, "close_all"):
+                h.close_all()
+
     def url(self):
         return self.path