Replace default.wav by a new ringtone

Original file name:
 - 171324__swidmark__ringtone.wav

Download location:
 - https://freesound.org/people/swidmark/sounds/171324

Uploader:
 - https://freesound.org/people/swidmark

License:
 - CC0 1.0 Universal (CC0 1.0)
 - https://creativecommons.org/publicdomain/zero/1.0

Change-Id: Ib521d600fd84d9038d80db8db2c32cb31817775d
Tuleap: #868

ringtones/default.wav.LICENSE

+Original file name: 171324__swidmark__ringtone.wav
+Download location: https://freesound.org/people/swidmark/sounds/171324
+Uploader: https://freesound.org/people/swidmark
+License: CC0 1.0 Universal (CC0 1.0) (https://creativecommons.org/publicdomain/zero/1.0/)