Unlimited players

A possible enhancement to the game would be to allow unlimited players.

This would greatly simplify the interface for when multiplayer is added, as any number of other users could connect and the host wouldn’t need to specify which players would be network players.

This does mean that new interactions need to be added for editing tanks that have already been put in the player list.

The issue names no files, tests, or entry points. Start by locating the player list and tank-editing interface, then determine the interactions needed for an unbounded list and how multiplayer connection setup should use it; done means unlimited players can be added and existing tanks can be edited.

Written by the indexing model from the issue text.