I was researching for quite some time how eo events could be made
faster, while doing that i recognized that we are not utilizing the full
size of Efl_Object_Data, so we can do a little bit more hinting for how
our events are currently working.
In this commit a flag called single priority is inserted. This flag
ensures that the object only has one callback priority registered, which
gives us the possibility of skipping the binary search, the search
itself is not that bad, however, alone the loading of the instructions
takes time, so this way we can skip the search, *and* the instructions
for moving the array elements to later.