Add support for Cepheus Atom and related systems like Barbaric!

[xdy]

Is your feature request related to a problem? Please describe.
I want to play a heavily mutated barbarian dwarf!

Describe the solution you'd like
Add these features to enable better support for the above.
Note that this issue contains a laundry list of things that each would useful separately. So, feel free to grab just part of this issue and create a new issue just for that part.
The ones that are struck through are done (though can certainly be improved).

• Add Cepheus Atom and Barbaric! to available systems
• Have a way to switch theming (CSS) based on selected system, and, actually have different theming for different systems.
• Either an alternate character sheet to support the Cepheus Atom-derived systems, or, maybe just have a flag to hide the unused attributes.
• Add Contamination to the template.json, and give it a field on the character sheet.
• Maybe switch some or all Mutations over to Traits if Implement Traits #272 ever gets done, possibly with Active Effect support.
• A setting to give a penalty to all actions when one suffers a Minor Wound, and code to support that. (I.e. give a -1 penalty to all skill rolls. Maybe using Active Effects, but, really, that would be overkill. A couple of changes in the damage handling code would probably suffice).
• Add compendiums and rollable tables (critical hits, mishaps, spells, etc) as appropriate

Describe alternatives you've considered
Don't add any code, the current documentation on how to handle it manually is reasonably clear.

Additional context
n/a

[xdy]

I'm fairly certain that the penalty on minor wound feature could be handled by using https://github.com/death-save/combat-utility-belt, though it might require Active Effect support.

[Lockbox313]

How are Barbaric! traits handled ?

[marvin9257]

How are Barbaric! traits handled ?

Sorry for the delay. I had not noticed this question. The short answer is that Traits can be added to the Traits section on the actor info tab. But because many of them have specific mechanistic implications, they won't have automation. This is a shortcoming of covering so many rulesets. Please ask on the Discord channel if you have further questions! Thanks.