patch 8.0.0713: 'termkey' option not fully implemented

Problem:    'termkey' option not fully implemented.
Solution:   Add initialisation.
diff --git a/src/version.c b/src/version.c
index 5080e2c..3640592 100644
--- a/src/version.c
+++ b/src/version.c
@@ -765,6 +765,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    713,
+/**/
     712,
 /**/
     711,