* The blue bird follows the same base AI as the red bird (it has a
target altitude that it tries to maintain, and it will dive at the
player) but the blue bird flies in a sine wave pattern around its
target altitude. It also has a longer scan radius to search for the
player than the red bird.
* The sine wave pattern of the blue bird means you may fly under its
radar depending how high it is on average.
Cheat codes that replace the player character are refactored to make
it easier to extend, and new cheats have been added:
* super azulian: play as the Red Azulian.
* hyper azulian: play as the White Azulian.
* bluebird: play as the new Bird (blue).
