Allow chains to use current/factory presets/settings

Also gives builtin effects a mean to determine if batch processing
is active, IsBatchProcessing() returns true if so.

src/effects/NoiseReduction.h

@@ -40,7 +40,7 @@ public:
 
 //   using Effect::TrackProgress;
 
-   virtual bool PromptUser(wxWindow *parent = NULL, bool isBatch = false);
+   virtual bool PromptUser(wxWindow *parent);
 
    virtual bool Init();
    virtual bool CheckWhetherSkipEffect();