add a "movetogroup" function, which hides the current window from

display and moves it to another group. useful with the recently added
"grouponly" function, giving the ability to use groups as simple
virtual desktops (similar to e.g. xmonad, dwm and scrotwm).

this doesn't have default keyboard bindings; cwmrc(5) now shows how
you could use these functions (use M-1...9 for grouponly1...9 and
MS-1...9 for movetogroup1...9 to emulate the default dwm bindings).

ok oga@

group.c

@@ -143,7 +143,16 @@ group_init(void)
 		TAILQ_INSERT_TAIL(&Groupq, &Groups[i], entry);
 	}
 
-	Group_active = &Groups[0];
+}
+
+void
+group_movetogroup(struct client_ctx *cc, int idx)
+{
+	if (idx < 0 || idx >= CALMWM_NGROUPS)
+		err(1, "group_movetogroup: index out of range (%d)", idx);
+
+	client_hide(cc);
+	_group_add(&Groups[idx], cc);
 }
 
 /*