Added Equalizer support on AudioEngine class

Two public methods added :
 * int equalizerBandCount()
 * bool setEqualizerBand(int band, int value)
One private method :
 * void initEqualizer()

Settings and GUI must be made in an external plugin

src/libtomahawk/audio/AudioEngine.cpp

@@ -224,8 +224,6 @@ AudioEngine::AudioEngine()
 
     d->mediaObject = new Phonon::MediaObject( this );
     d->audioOutput = new Phonon::AudioOutput( Phonon::MusicCategory, this );
-    d->audioDataOutput = new Phonon::AudioDataOutput( this );
-
     d->audioPath = Phonon::createPath( d->mediaObject, d->audioOutput );
 
     d->mediaObject->setTickInterval( 150 );
@@ -238,7 +236,7 @@ AudioEngine::AudioEngine()
     onVolumeChanged( d->audioOutput->volume() );
     setVolume( TomahawkSettings::instance()->volume() );
 
-    // initEqualizer();
+    initEqualizer();
 }
 
 
@@ -1391,9 +1389,10 @@ AudioEngine::initEqualizer()
     Q_D( AudioEngine );
 
     QList<Phonon::EffectDescription> effectDescriptions = Phonon::BackendCapabilities::availableAudioEffects();
+    d->audioEffect = NULL;
     foreach(Phonon::EffectDescription effectDesc, effectDescriptions)
     {
-        if ( effectDesc.name().toLower().contains( "eq" ) )
+        if(effectDesc.name().contains("Eq") || effectDesc.name().contains("eq"))
         {
             d->audioEffect = new Phonon::Effect(effectDesc);
             d->audioPath.insertEffect(d->audioEffect);

src/libtomahawk/audio/AudioEngine.h

@@ -200,6 +200,7 @@ private slots:
 private:
     void setState( AudioState state );
     void setCurrentTrackPlaylist( const Tomahawk::playlistinterface_ptr& playlist );
+    void initEqualizer();
 
     void initEqualizer();
     void audioDataArrived( QMap< AudioEngine::AudioChannel, QVector< qint16 > >& data );

src/libtomahawk/audio/AudioEngine_p.h

@@ -1,9 +1,8 @@
 
 #include <phonon/MediaObject>
 #include <phonon/AudioOutput>
-#include <phonon/AudioDataOutput>
-#include <phonon/BackendCapabilities>
 #include <phonon/Path>
+#include <phonon/BackendCapabilities>
 #include <phonon/Effect>
 #include <phonon/EffectParameter>
 
@@ -44,6 +43,8 @@ private:
 
     Phonon::MediaObject* mediaObject;
     Phonon::AudioOutput* audioOutput;
+    Phonon::Path audioPath;
+	Phonon::Effect* audioEffect;
 
     Phonon::Path audioPath;
     Phonon::Effect* audioEffect;