After speaking with the C# devs, it is clear that code gen is not ready.
I can get around this by doing the following:
1. Creating a library
2. Splitting out the schema writing from the source generator
3. Moving the schema loading to `AdditionalFiles`
4. Writing a new post-build application using Roslyn to write the schema files after building.
- [X] Caches DateTime.NowUtc on the game loop (not other threads)
- [X] Replaces all locations where it makes sense
- [X] Adds Min/Max for `IComparable` (TimeSpan, DateTimes, etc)
Closes#261
