Create an GODefinition object, which stores "type" information for different objects

[zackthehuman]

A GameObject instance is an instance of an object in the world. For each object type, there is a set of properties that are intrinsic to the type, and there are instance properties. Instance properties will be part of the GameObject, but other things that are "static" need to be stored somewhere else.

That "somewhere else" is the GODefinition object. There is one definition object per game object type. The game object instances have a read-only pointer back to their definition.

This allows for two things:

• Keeps GameObject free from properties that are "set once" and never modified
• Allows for interesting runtime changes like instantly changing all instances of a type by modifying the definition