Feat/reworked language codes (#865)

* Reworked language codes to use Steam localization standards

* Reworked language codes tweaks (#864)

* Language code rework tweaks

* Update bg.lua

* Reevaluate whether a language is WIP

* Update bg.lua

* Even better mark for languages as WIP (> 80% translated)

* Update zh_cn.lua

* Update cs.lua

* Fix for game language codes

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Co-authored-by: kittenchilly <mario.pikmin.zelda@gmail.com>

CREDITS.md

@@ -4,7 +4,7 @@ If you enjoy this mod and want to help on it, check it out on GitHub: https://gi
 
 # Languages
 - **Bulgarian**: by TST_Gogo_, Gothika_47
-- **Chinese**: by Xheepey87, frto027
+- **Chinese (Simplified)**: by Xheepey87, frto027
 - **Czech**: by David Kapitančik. Picus, domcizzz
 - **Dutch**: by SomethingMax
 - **English**: by Wofsauge, Buurazu, Ma-rcx, AutisticGoat (Kotry), ...
@@ -19,7 +19,7 @@ If you enjoy this mod and want to help on it, check it out on GitHub: https://gi
 - **Romanian**: by  ed._.096, MHI
 - **Russian**: by hell2Pay, fly_6, Dezzelshipc and Sekaz
 - **Spanish**: by Lidia Arroyo Purroy, MartinFierro, maintained by AutisticGoat (Kotry)
-- **Brazilian - Portuguese**: by LuanRoger and NotZin02
+- **Brazilian Portuguese**: by LuanRoger and NotZin02
 - **Turkish**: by Cagdas Salur, Mert Dutal
 - **Ukrainian**: by x3xto
 - **Vietnamese**: by Hanzo