Adding an empty cell to define boundaries when these are in a grid instead of using null.  Make neighbors public again since I'll need it very shortly.
Actually I don't need an empty cell.  Was silly to add it too soon.
remove the overridden equals method.  Its bad to implement equals just for tests and I should know better.  Plus the only equality I will really care about is if they're the same in memory object in a grid.
Add the first chunk of the grid class.  Can create a nxn grid of dead cells that are all properly linked with their neighbors.