actors → registry Relation

File in src/engine/actors	Includes file in src/engine/registry
Cloud.h	RegisterContent.h
FallingRock.h	RegisterContent.h
Finishline.h	RegisterContent.h
MarioSign.h	RegisterContent.h
Ship.h	RegisterContent.h
SpaghettiShip.h	RegisterContent.h
Starship.h	RegisterContent.h
Text.h	RegisterContent.h
WarioSign.h	RegisterContent.h