|SOURCE|
[Common::GameEntity::GameEntityType]
* Parameterised constructor takes a ZED_BOOL to determine if this entity is
  unique or if multiple instances may exist in the world
* Added an equality operator, which will return ZED_FALSE if either the name or
  the ID from the parameter do not match, otherwise ZED_TRUE is returned
* IsUnique returns whether multiple instances of this type are allowed
* The default constructor sets the unique attribute to ZED_FALSE

[Common::GameEntity]
* GetGameEntityType returns the GameEntityType into the parameter passed in
[Common::GameEntityManager]
* PurgeEntities will clean up the memory used by the entities in the entity
  array
* Added a unique ID which is assigned to new game objects
* CreateEntity takes the entity's uniqueness into account when creating a new
  instance, if an instance already exists and it is unique, then the new one is
  not added and ZED_FAIL is returned
[Common::GameplayGameState]
* Added a GameEntityManager to oversee the lifecycle of game entities
* Added a Player to the GameEntityManager instance
[Common::Player]
* PlayerGameEntityType initialised as being unique
|SOURCE|
[Common::GameEntity::GameEntityType]
* The copy constructor sets the unique attribute according to the original
  version passed in
* The assignment operator sets the unique attribute according to the
  GameEntityType passed in