Fix play/pause when stopped

Sending the 'pause' command has no effect if the player is currently
stopped. Thus, 'play' must be sent explicitly in that case.

src/mpdnotify.py

@@ -147,8 +147,10 @@ class Notifier(object):
     def bind_keys(self):
         def playpause():
             status = self.client.status()
-            pause = int(status['state'] == 'play')
-            self.client.pause(pause)
+            if status['state'] == 'stop':
+                self.client.play()
+            else:
+                self.client.pause()
 
         def volume_down():
             status = self.client.status()