Document "o"/"opponent" command for blind mode
Document "o"/"opponent" command for blind mode

Command was already in place but undocumented and so unknown by players. For #6401

arex1337/lila,arex1337/lila,arex1337/lila,luanlv/lila,luanlv/lila,luanlv/lila,arex1337/lila,luanlv/lila,arex1337/lila,arex1337/lila,luanlv/lila,luanlv/lila,arex1337/lila,luanlv/lila