patch 8.2.0425: code for modeless selection not sufficiently tested

Problem:    Code for modeless selection not sufficiently tested.
Solution:   Add tests.  Move mouse code functionality to a common script file.
            (Yegappan Lakshmanan, closes #5821)
diff --git a/src/version.c b/src/version.c
index 166c1d4..fbd039b 100644
--- a/src/version.c
+++ b/src/version.c
@@ -739,6 +739,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    425,
+/**/
     424,
 /**/
     423,