Fix entity placement test failing.

[dmccoystephenson]

After placing an entity into an environment, the number of entities in that environment is not verified to be non-zero.

[dmccoystephenson]

I don't know why this is failing.

Entity entity("Daniel");
Environment environment("Earth", 2);
environment.addEntity(entity);
int numEntities = environment.getNumEntities();
int expectedNumEntities = 1;
assert(numEntities == expectedNumEntities);

[dmccoystephenson]

I've modified the test now to check if the entity is present, rather than checking the number of entities. It is still failing. Placement doesn't work for some reason.

[dmccoystephenson]

References!