Clarify the issue with spaces in device name, closes #146.

README.md

@@ -46,7 +46,7 @@ device = alsa_audio_device # Given by `aplay -L`
 mixer = PCM
 volume-control = alsa # or alsa_linear, or softvol
 #onevent = command_run_on_playback_event
-device_name = name_in_spotify_connect
+device_name = name_in_spotify_connect # Cannot contain spaces
 bitrate = 96|160|320
 cache_path = cache_directory
 volume-normalisation = true