epic(setup): Base Payment Rate as Function of Ether Price

[0x4007]

We can make pricing more competitive/accurate based on how high the market is. We all know that in a bull market its harder to convince devs to work on your crypto project.

https://github.com/ubiquity/bounty-bot/blob/e743239e69b7bbdc9a91eef20ccf8c3a166ab223/src/configs/price.ts#L4

We have a base rate here which could be a proxy for the current price of Ether. If ETH is at $2000, then our smallest bounties (as of writing this, currently looking to introduce an even smaller bounty size) can go up from $100 -> $200 for example.

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I think its important to make sure that each project can configure what pricing strategy/formula/algorithm they deploy for each repo, as perhaps some projects would be less keen on being as competitive. I think our current strategy of set prices is simple to comprehend for most projects, but I would love to enable this "market price/dynamic pricing" as sort of an "opt-in" feature.

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The price of Ether is a generic/simple/top-of-mind quantity I'm using here, but I believe that perhaps we could consider including the entire crypto market cap as well. I think for the foreseeable future, using the price of Ether as an oracle is sufficient.

[0x4007]

This could lead to a mess with custom/obscure prices. We could quantize prices to be at $50 increments to make it look neater!