add inverse of util.os_path for canonical path generation

sphinx/util/osutil.py

@@ -39,6 +39,10 @@ SEP = "/"
 def os_path(canonicalpath):
     return canonicalpath.replace(SEP, path.sep)
     
+def canon_path(nativepath):
+    """Return path in OS-independent form"""
+    return nativepath.replace(path.sep, SEP)
+
 
 def relative_uri(base, to):
     """Return a relative URL from ``base`` to ``to``."""