With this new API the user can block movements on X axis, Y Axis or
both. I was left with no option but to come up with this, side by side
with elm_object_scroll_freeze_push(), elm_object_scroll_hold_push()
and elm_object_scroll_lock_x_set() (or
elm_object_scroll_lock_y_set()), once all of these will act on *parent
and/or child* widgets too, making those useless for any pratical use
of scroll blocking. Here's a sane, new option, enjoy it.