Make our own server rules prototype

[TGRCdev]

Continuation of #851. We discovered that the CVars contain a place to define which ruleset prototype to use as the server rules. With this knowledge, we should restore the upstream rule prototypes, create our own prototypes, and set the server.rules_file CVar to point to it. This will protect us from upstream merge conflicts if wizden decides to update their rules.

[TGRCdev]

Pinging @mqole, since you've got the most recent experience working with the rules structure