feat: board integration, autosubmit refactor

[hero622]

Integrate boards into the in-game leaderboards.

• Runs in top 40 are shown.
• Autorenders can be opened by clicking on a run.
• Gets around the issue of Steam boards being down.

Technical stuff

• Merged AutoSubmit and AutoSubmitMod, everything uses the autosubmit.key format (first line for website URL, second line for key), this should be changed on the main boards website as the download.
• top-scores API (from Mel boards) needs to be implemented to main boards (so we can actually display top 40 scores around the player).
• Map IDs for base game should be moved to the website as an API endpoint (similarly to Mel).
• FIXME: Heap gets corrupted on run finish, something goes wrong with freeing the avatar images.
• Autorender opening currently only works in games with updated Steam APIs.

Notes

• I left xrefs in as comments for some stuff so they are easier to find if needed (I assume atleast some of the sigs are going to be different for linux mods).
• Code is written in a way that in the future if we want to, it's easy to implement LP boards too.

[hero622]

Just added option to store all keys in the same file (useful for p2common users), e.g.:

board.portal2.sr
key1
mel.board.portal2.sr
key2

And now key files with old format get automatically converted to new one, accounting for the change I just made.

[ThisAMJ]

p2sr/Portal2Boards@e0df39d

don't plan on merging until the crash is fixed and LP is supported (maybe just use the builtin lp thing if that's possible)
and all da mods