Removed old definitions from commands.h

commands.h

@@ -64,9 +64,6 @@ bool i_fit_to_win(arg_t);
 bool i_fit_to_img(arg_t);
 bool i_rotate(arg_t);
 bool i_flip(arg_t);
-bool i_toggle_slideshow(arg_t);
-bool i_adjust_slideshow(arg_t);
-bool i_reset_slideshow(arg_t);
 bool i_toggle_antialias(arg_t);
 bool it_toggle_alpha(arg_t);
 bool it_open_with(arg_t);