Turn almost all Listeners into abstract interfaces

rtgui/bayerpreprocess.cc

@@ -134,6 +134,10 @@ void BayerPreProcess::adjusterChanged (Adjuster* a, double newval)
     }
 }
 
+void BayerPreProcess::adjusterAutoToggled(Adjuster* a, bool newval)
+{
+}
+
 void BayerPreProcess::setBatchMode(bool batchMode)
 {
     ToolPanel::setBatchMode (batchMode);