OMG, such declarative!
avoid operator/
rename {generate,create}_bitmap

We do not genrate there anything. Just create.
rename generate_{enemy,unit}_bitmap

We could generate ships' bitmaps using this function. So no need
to encode enemy name here.
geneate players' ships too
add generate_unit, don't duplicate code
no longer need for resouces as they are auto generated
fix alpha blending for generated textures
fast enemy is purple :)
second player is blue