Improvments to gstreamer backend and settings +++

- Fixed bug not setting environment for gstreamer before initialization
- Fixed windows directsound device
- Fixed crash on failure to create gstreamer element
- Fixed crash when switching backend
- Don't stop playback if equalizer or replay gain fails in gstreamer
- Improvments to backend settings
- Fixed backend settings to work for windows
- Fixed replay gain settings not working
- Fixed right click menu for album showing in statusview even when no song was playing
- Removed redundant code

src/engine/alsadevicefinder.cpp

@@ -97,12 +97,9 @@ QList<DeviceFinder::Device> AlsaDeviceFinder::ListDevices() {
       snd_pcm_info_get_name(pcminfo);
 
       Device device;
-      device.card = card;
-      device.device = dev;
       device.description = QString("%1 %2").arg(snd_ctl_card_info_get_name(cardinfo)).arg(snd_pcm_info_get_name(pcminfo));
-      device.string = QString("hw:%1,%2").arg(card).arg(dev);
-      device.device_property_value = QString("hw:%1,%2").arg(card).arg(dev);
-      device.iconname = GuessIconName("", device.description);
+      device.value = QString("hw:%1,%2").arg(card).arg(dev);
+      device.iconname = GuessIconName(device.description);
       ret.append(device);
 
     }