TITANIC: Removed const modifier from all saveable objects

Turns out that CGameObject::save regenerates the _movieRangeInfo list.
So the const suffix can no longer be used for the entire hierarchy

engines/titanic/game/fan_decrease.cpp

@@ -24,7 +24,7 @@
 
 namespace Titanic {
 
-void CFanDecrease::save(SimpleFile *file, int indent) const {
+void CFanDecrease::save(SimpleFile *file, int indent) {
 	file->writeNumberLine(1, indent);
 	CGameObject::save(file, indent);
 }