feat: Allow resources to be cached

[oliversalzburg]

I feel like this was someone's intention all along. I just tied all the pieces together. When a new release is published yarn run build should be used to bump the revision. Then that is used to construct the cache-breaking URL query parameter. This way the client only need to pull the resources once for every version of KG.

I wasn't able to test this yet.

[hyx3179]

ServiceWorker may be a better solution. My own version uses this technology.
https://github.com/hyx3179/kittensgame/blob/fd2583d7d0210961ec88cc14f628470bcf1f30af/sw.js
https://github.com/hyx3179/kittensgame/blob/fd2583d7d0210961ec88cc14f628470bcf1f30af/index.html#L6
I'll sort out the relevant code when I have time.

[oliversalzburg]

Oh, fancy solution. Very nice.

I'd probably have to clean this PR up anyway, but it didn't seem like there was much interest to merge this 😄

[hyx3179]

Most of the client's demand for this feature comes from slow loading. It often takes more than 1 minute to load the official website where I am, and network errors often occur and the website cannot be loaded. 😂
If the server is charged by bandwidth, there may not be much demand for this feature.

[oliversalzburg]

I restored the simple change on top of master. It's not great, but it's something.

[oliversalzburg]

@hyx3179 I agree, ServiceWorker seems like the all-around best solution. Maybe @bloodrizer wants to adopt that in the future, but I don't believe I can achieve much here. I'll close this in favor of a proper solution in the future.