shutil: Don't allow an empty string in rmtree.

python-stdlib/shutil/manifest.py

@@ -1,3 +1,3 @@
-metadata(version="0.0.4")
+metadata(version="0.0.5")
 
 module("shutil.py")

python-stdlib/shutil/shutil.py

@@ -6,6 +6,9 @@ _ntuple_diskusage = namedtuple("usage", ("total", "used", "free"))
 
 
 def rmtree(d):
+    if not d:
+        raise ValueError
+
     for name, type, *_ in os.ilistdir(d):
         path = d + "/" + name
         if type & 0x4000:  # dir