Fix and improve BAR_WINTITLEACTIONS_PATCH (#442)

Introduced an unhideall function that can be used to reveal all hidden client in the current view.

Added a change to unmanage to avoid changing the window state from IconicState to WithdrawnState when the window manager stops managing windows (which happens when restarting).

Previously a hidden window would disappear when restarting dwm because:
   - when hidden the window would be unmapped and having the window state of IconicState
   - when restarting the window would remain unmapped while the window state would become WithdrawnState
   - which would prevent the window from being picked up by the scan function when the window manager starts

config.def.h

@@ -1165,6 +1165,7 @@ static const Key keys[] = {
 	#endif // SHIFTSWAPTAGS_PATCH
 	#if BAR_WINTITLEACTIONS_PATCH
 	{ MODKEY|ControlMask,           XK_z,          showhideclient,         {0} },
+	{ MODKEY|ControlMask,           XK_s,          unhideall,              {0} },
 	#endif // BAR_WINTITLEACTIONS_PATCH
 	{ MODKEY|ShiftMask,             XK_c,          killclient,             {0} },
 	#if KILLUNSEL_PATCH