Update beets to 1.4.7

Also updates:
- colorama-0.4.1
- jellyfish-0.6.1
- munkres-1.0.12
- musicbrainzngs-0.6
- mutagen-1.41.1
- pyyaml-3.13
- six-1.12.0
- unidecode-1.0.23

libs/beetsplug/fuzzy.py

@@ -44,5 +44,5 @@ class FuzzyPlugin(BeetsPlugin):
         })
 
     def queries(self):
-        prefix = self.config['prefix'].get(basestring)
+        prefix = self.config['prefix'].as_str()
         return {prefix: FuzzyQuery}