bart_ticking_clock:

Copyright information:

-   Origin: <https://opengameart.org/content/ticking-clock>
-   Author: bart
-   License: CC0: <https://creativecommons.org/publicdomain/zero/1.0/>

Changes from original (licensed under same terms as the entire project):

-   Doubled in length
-   Noise reduced
-   Reverb added (Audacity; defaults + 100% room size + 90%
    reverberance)
-   Normalized
-   Fade in (quadratic) over the first half
