patch 8.0.0813: cannot use a terminal window while the job is running

Problem:    Cannot use Vim commands in a terminal window while the job is
            running.
Solution:   Implement Terminal Normal mode.
diff --git a/src/normal.c b/src/normal.c
index c8e7841..e8f80f1 100644
--- a/src/normal.c
+++ b/src/normal.c
@@ -9037,6 +9037,14 @@
     static void
 nv_edit(cmdarg_T *cap)
 {
+#ifdef FEAT_TERMINAL
+    if (term_in_terminal_mode())
+    {
+	term_leave_terminal_mode();
+	return;
+    }
+#endif
+
     /* <Insert> is equal to "i" */
     if (cap->cmdchar == K_INS || cap->cmdchar == K_KINS)
 	cap->cmdchar = 'i';