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/covermanager/discogscoverprovider.cpp

@@ -118,7 +118,7 @@ void DiscogsCoverProvider::SendSearchRequest(DiscogsCoverSearchContext *s_ctx) {
   }
 
   // Sign the request
-  const QByteArray data_to_sign = QString("GET\n%1\n%2\n%3").arg(url.host(), url.path(), query_items.join("&")).toLatin1();
+  const QByteArray data_to_sign = QString("GET\n%1\n%2\n%3").arg(url.host(), url.path(), query_items.join("&")).toUtf8();
   const QByteArray signature(Utilities::HmacSha256(QByteArray::fromBase64(kSecretKeyB64), data_to_sign));
 
   // Add the signature to the request