Update pp calculations

[delan]

This patch updates the pp calculations in osuplus to use Francesco149/ojsama, which is more up to date than osuck, but not up to date with the most recent pp changes. There’s another library that’s fully up to date, but osuplus would need some bigger changes before we can switch to that, so let me know and we can discuss.

ojsama only supports standard mode, but so does osuck, so I’ve replaced the osuck code entirely. Note that ojsama doesn’t use @require, because it exports everything in an “osu” object, which the site also uses for its own stuff.

doPpcalc is basically the interesting part. It replaces the old getPpCalc, and it handles downloading the beatmap file, parsing it, and calculating pp and pp if full combo.

As a bonus, this makes pp calculations for multiple plays of the same beatmap instant.