Add Player support

[alecho]

Is your feature request related to a problem? Please describe.
Currently, players are identified by their color atom and this is all Chex knows about.

Describe the solution you'd like
Add support for assigning arbitrary terms to each color to be used to identify players and add functions around that value. This could be a simple string, user id, session id, etc.

Describe alternatives you've considered
Make library consumers track player state and who is assigned to each color.

Additional context
https://www.theerlangelist.com/article/spawn_or_not