[openbox] Default ShowMenu posision

[Alexey Korop]

Hi, All

  The "ShowMenu" action allow now (3.6) to define the menu position. But
there are two very different ways to call the menu - by mousebind and by
keybind. For me optimal placement for the "mousebind menus" is in under
mouse pointer and for the "keybind menus" - the screen center.
  Is there a way to define for the keybinds and for the mousebinds
separate default MenuShow positions?

Yours truly Alexey