Implemented purple playback bar for Podcasts

- Added a settings toggle for it
- Added 1 language string to en_US and the i18n README
- Translated string to hu_HU
- Changed CSS background color for playback bar dot to songProgressColor

src/main/base/store.ts

@@ -209,7 +209,8 @@ export class Store {
             "uiScale": 1.0,
             "windowColor": "#000000",
             "customAccentColor": false,
-            "accentColor": "#fc3c44"
+            "accentColor": "#fc3c44",
+            "purplePodcastPlaybackBar": false
         },
         "lyrics": {
             "enable_mxm": false,