code: @Override
      public void removeAllVariables() {
          List<RoomVariable> vars = room.getVariables();
          for(RoomVariable var : vars) var.setNull();
          api.setRoomVariables(null, room, vars, true, true, false);
      }
docs: /* (non-Javadoc)
  @see com.tvd12.ezyfox.core.command.UpdateRoomInfo#removeAllVariables()