Enable whipper to use track title if possible

track.title = t.get('title', t['recording']['title']).

Since if a track itself doesn't have a title then the track
title is the same with the recording title. Otherwise, a track
has its own title then t['title'] is different from
t['recording']['title'] and whipper chooses t['title'].

[Fixes whipper-team#192]
Signed-off-by: ABCbum <kimlong221002@gmail.com>

whipper/common/mbngs.py

@@ -247,7 +247,7 @@ def _getMetadata(release, discid, country=None):
                     track.sortName = trackCredit.getSortName()
                     track.mbidArtist = trackCredit.getIds()
 
-                    track.title = t['recording']['title']
+                    track.title = t.get('title', t['recording']['title'])
                     track.mbid = t['id']
                     track.mbidRecording = t['recording']['id']
                     track.mbidWorks = _getWorks(t['recording'])