Swiss r520

Swiss r520 is released. The swiss army knife of gamecube homebrew. Swiss aims to be the ultimate utility Gamecube homebrew application.

Swiss Changelog:
Big revision jump here since I've merged in my gui-rewrite branch which included a backend GUI rewrite to support a threaded UI amongst other fixes. There will likely be bugs in the rewritten GUI which I'll need to iron out as more people start to use it.

@Extrems changes:

Improve PAL 50Hz forcing.
@Streetwalrus changes:

Build fixes
@emukidid changes:

GUI rewritten to be threaded, will make more advanced UI functionality possible
Fix SD (non HC/XC) issues when running games
Compile with latest libOGC/devkitPPC
Fix device init issue where device size would zero out
Fix SDGecko being locked at 16MHz when it was the default device
Fix issue where pressing up/down on device select caused weird behaviour
Fix multi-game disc sizing
Fix DVD device size calculations

download https://github.com/emukidid/swiss-gc

via http://www.emucr.com/2018/12/swiss-r520.html