Issue #16752: Add a missing import to modulefinder.

Also fix Misc/ACKS to put part of it back in alphabetical order and
remove some duplicate names.

Patch by Berker Peksag.
diff --git a/Lib/modulefinder.py b/Lib/modulefinder.py
index 683e305..f90a432 100644
--- a/Lib/modulefinder.py
+++ b/Lib/modulefinder.py
@@ -2,6 +2,7 @@
 
 import dis
 import imp
+import importlib.machinery
 import marshal
 import os
 import sys