Merge pull request #245 from sochotnicky/master

Update mutagen dependency to 0.21

setup.py

@@ -71,7 +71,7 @@ setup(name='beets',
       },
 
       install_requires=[
-          'mutagen>=1.20',
+          'mutagen>=1.21',
           'munkres',
           'unidecode',
           'musicbrainzngs>=0.3',

test/testall.py

@@ -24,6 +24,13 @@ pkgpath = os.path.dirname(__file__) or '.'
 sys.path.append(pkgpath)
 os.chdir(pkgpath)
 
+# Make sure we use local version of beetsplug and not system namespaced version
+# for tests
+try:
+    del sys.modules["beetsplug"]
+except KeyError:
+    pass
+
 def suite():
     s = unittest.TestSuite()
     # Get the suite() of every module in this directory beginning with