Corrected shooting positions of most shooting enemies. (E.g. the turtle tanks in fanolint and technoir did not work correctly.) Bullets will now shoot from the position that was set in the attack animation.

sprite.h, sprite.cpp
*) Changed draw method to include a parameter to enable or disable the drawing of sprite offsets (bullets do not use these offsets). The default behavior is to add the offset. 

bullet.cpp
*) Changed the draw method to disable sprite offsets, using the parameter that was mentioned earlier.
*) Slightly changed the way the y position of the bullet is determined in the event constructor.