Augmented Steam от IsThereAnyDeal

tl;dr:
- improved accuracy of current card prices by removing the dependency on Augmented Steam server
- refactored market stats, they should be more reliable now, but I don't have large market history to properly test it on
so let me know if I broke it
- removed booster averages and worth on badge page

Steam has been making it increasingly hard to query market with throttling. You've probably seen this
with some features that stopped working because of too many requests.

It got to the point where we have to drop some of the features, because claiming we do have them is almost becoming a lie,
but I'll try to keep what I can.

I had to remove card averages and worth computation, because that relied on a server crawling market and fetching current prices.
With Steam's throttling this has become increasingly less accurate over time.

In badge detail page I've moved fetching of current prices to extension instead of fetching them from server,
Same thing that Steam does for inventory. If you check many badges in quick succession, this may lead to throttling though,
so we'll see how this works.

Lastly, I've refactored market stats. They should not be trying to fetch pages as aggressively as they were,
and it should be more robust. Even if it does not manage to fetch your entire history at once, once you can make requests again
it should continue where it ended. I don't have large market history to test this properly, so let me know
in case of issues.