Qt: Add GUI for game-specific settings (#3533)

* Open settings dialog from context menu

* initial version complete

* add context menu item to delete game config if it exists

* Create game config from base value instead of default value

* Require confirmation before deleting game configs with menu item

* fix rebase

* Reset game specific values when creating a new game config

* Add icon for entries with game config

* clang format

* Add submenu for game-specific settings

* Log if game-specific config exists, remove hidden tab from tab selection

* Add other experimental options to game-specific GUI

* clang format

* Add flag to specify if game-specific file needs creation

* refactor: remove additional arguments, reset game-specific status on save instead

* Fix return

* cleanup - remove unneeded load

* Set tab to general if hidden tab is set as default

* Cleanup variable names and strings, default tab fix, volumeslider fix

* cleanup: missed a couple of variables to standardize

* More readable way to reset volume slider

REUSE.toml

@@ -74,6 +74,7 @@ path = [
     "src/images/youtube.svg",
     "src/images/trophy.wav",
     "src/images/hotkey.png",
+    "src/images/game_settings.png",
     "src/shadps4.qrc",
     "src/shadps4.rc",
     "src/qt_gui/translations/update_translation.sh",