Add Spanish localization for menu, moves and pokeballs

src/system/settings.ts

@@ -176,6 +176,10 @@ export function setSetting(scene: BattleScene, setting: Setting, value: integer)
                 label: 'English',
                 handler: () => changeLocaleHandler('en')
               },
+              {
+                label: 'Spanish',
+                handler: () => changeLocaleHandler('es')
+              },
               {
                 label: 'French',
                 handler: () => changeLocaleHandler('fr')