Issue #19023: Document ctypes array and pointer classes

Also add some more tests. Based on patch by Sye van der Veen.
diff --git a/Misc/ACKS b/Misc/ACKS
index 2ceb041..0a71085 100644
--- a/Misc/ACKS
+++ b/Misc/ACKS
@@ -1418,6 +1418,7 @@
 Sebastian Ortiz Vasquez
 Alexandre Vassalotti
 Nadeem Vawda
+Sye van der Veen
 Frank Vercruesse
 Mike Verdone
 Jaap Vermeulen