Turn page while playing (#1383) fixes #1365

* Add an EReader setting for turning when playing

This allows to allow the navigation with the Volume buttons even when
audiobooks are playing.

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Co-authored-by: advplyr <advplyr@protonmail.com>

strings/nl.json

@@ -176,8 +176,6 @@
   "LabelNarrator": "Verteller",
   "LabelNarrators": "Vertellers",
   "LabelNavigateWithVolume": "Navigeer met volume knoppen",
-  "LabelNavigateWithVolumeDisabled": "Uit",
-  "LabelNavigateWithVolumeEnabled": "Aam",
   "LabelNavigateWithVolumeMirrored": "Gespiegeld",
   "LabelNever": "Nooit",
   "LabelNewestAuthors": "Nieuwste Auteurs",
@@ -186,6 +184,7 @@
   "LabelNotFinished": "Niet Voltooid",
   "LabelNotStarted": "Niet Gestart",
   "LabelOff": "Uit",
+  "LabelOn": "Aan",
   "LabelPassword": "Wachtwoord",
   "LabelPath": "Pad",
   "LabelPlaybackDirect": "Direct",