Game specific configs (#3376)

* poc

* Set up variable game specific variable copies

* Set up getters to return the game specific option if it exists

* Avoid exceptions if a value isn't in the config

* Make sure the custom configs folder exists

* Update + review comments + rewrite

* The loathsome clang-formatter

* Specify which getter/setter is used everywhere

src/emulator.cpp

@@ -114,6 +114,9 @@ void Emulator::Run(std::filesystem::path file, const std::vector<std::string> ar
         }
     }
 
+    Config::load(Common::FS::GetUserPath(Common::FS::PathType::CustomConfigs) / (id + ".toml"),
+                 true);
+
     // Initialize logging as soon as possible
     if (!id.empty() && Config::getSeparateLogFilesEnabled()) {
         Common::Log::Initialize(id + ".log");