enemy stuff

halved shooting rate, redid falling in pit, bullets pass through after
killing them
Enemy bullet collisions

enemy bullets now kill megaman
more bullet/collisions stuff

fixed a collision issue with falling enemies where falling enemies would
die if they fell onto the y value of a bullet even if it had gone past
them, fixed the issue where enemies would build up and shoot multiple
bullets
enemy level issue fix and magic numbers

set an if in the enemies class so they update based on the level, like
in the draw method, set frame numbers to vars to get rid of the magic
numbers for them