patch 8.2.1978: making a mapping work in all modes is complicated

Problem:    Making a mapping work in all modes is complicated.
Solution:   Add the <Cmd> special key. (Yegappan Lakshmanan, closes #7282,
            closes 4784, based on patch by Bjorn Linse)

src/ex_docmd.c

@@ -8148,6 +8148,9 @@ ex_startinsert(exarg_T *eap)
 	    restart_edit = 'i';
 	curwin->w_curswant = 0;	    // avoid MAXCOL
     }
+
+    if (VIsual_active)
+	showmode();
 }
 
 /*