patch 8.0.0419: test for v:progpath fails on MS-Windows

Problem:    Test for v:progpath fails on MS-Windows.
Solution:   Expand to full path.  Also add ".exe" when the path is an absolute
            path.
diff --git a/src/version.c b/src/version.c
index 6558b01..834f144 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    419,
+/**/
     418,
 /**/
     417,