Random API

Dice, shuffling etc. all require randomness, but having impure reducers (using Math.random(), for example) breaks the ability to view earlier game states (and is an anti-pattern in Redux). We should use a seed in ctx (that’s stripped away before sending it to the client) that is used to predictably generate random numbers.

Plan:

• API to generate random numbers.
• API for various die rolls.
• API to shuffle an array.
• Allow calling the Random API in flow code (only really supported in moves at the moment).

[nicolodavis]

Yep, sounds good. I’m happy to make the necessary changes to your PR before merging it in too.

[Stefan-Hanke]

OK. Turns out that test used plain numbers for G. I hope you don’t mind that I changed it to be an object with one key arg.

I’m royally unsure about my changes in the rollup config.