Add two new files and update remaining tests from the latest update of the
test suite in version 2.39 of dectest.zip.
diff --git a/Lib/test/decimaltestdata/plus.decTest b/Lib/test/decimaltestdata/plus.decTest
index f331901..a6d8e58 100644
--- a/Lib/test/decimaltestdata/plus.decTest
+++ b/Lib/test/decimaltestdata/plus.decTest
@@ -17,7 +17,7 @@
 --   IBM UK, PO Box 31, Birmingham Road, Warwick CV34 5JL, UK         --
 --   mfc@uk.ibm.com                                                   --
 ------------------------------------------------------------------------
-version: 2.38
+version: 2.39
 
 -- This set of tests primarily tests the existence of the operator.
 -- Addition and rounding, and most overflows, are tested elsewhere.