Implement player scores

[sburnicki]

Traze currently lacks any support of scores or statistics about player performance.
We want to implement a rating-based scoring system in order to compare the performance of different bots and players.
The scoring should meet the following requirements:

• User should keep the scores even when leaving the game
• Scores should be in a limited range (e.g. from 0 to 1000)
• New players should be able to compete with long-lived players

[asciijungle]

We could use a modified version of the ELO rating system used in chess.
Something like described in this article:
https://gamedesignerkid.blogspot.com/2017/05/hi-guys-youve-been-waiting-long-so.html

[mgerhardy]

Do I have to implement a sign-up and login in my own client, then?