Fix playback of local non-MPD files under Windows.

Issue #1250

ChangeLog

@@ -10,6 +10,7 @@
 7. For windows, when adding local files (served via internal HTTP server) add
    the real file path as a query item.
 8. Use smaller text for help text in Tweaks section of preferences dialog.
+9. Fix playback of local non-MPD files under Windows.
 
 2.3.0
 -----

http/httpserver.cpp

@@ -172,6 +172,7 @@ QByteArray HttpServer::encodeUrl(const Song &s)
     #ifdef Q_OS_WIN
     // Use a query item, as s.file might have a driver specifier
     query.addQueryItem("file", s.file);
+    url.setPath("/"+Utils::getFile(s.file));
     #else
     url.setPath(s.file);
     #endif