refactor event schedulers to use explicit game rules

[IProduceWidgets]

About the PR

Refactors basic & ramping event scheduler to take explicit event definitions in yml instead of just doing whatever the hell they wanted to. Also added a new RandomRuleSystem for selecting and running a random gamerule from an explicit list of gamerules.

Why / Balance

Shuttle events, gift events, the desire to add things that shouldn't be in event schedulers. I cannot overstate how many levers this adds to event balancing by using combinations of multiple schedulers and RandomEvents which both accept orGroups and weights.

Technical details

Media

• [x] I have added screenshots/videos to this PR showcasing its changes ingame, or this PR does not require an ingame showcase

Breaking changes

If you have events you want run via the basic/ramping event scheduler, they need to be defined explicitly now.

Changelog

no player facing changes, except that maybe cargo gifts and unknown shuttle events will be much less likely.