Stop incorrectly calling CC0 a license

CC0 is a public domain dedication, not a license [1]. In the world of
FOSS, the term “license” is primarily used to refer to a “copyright
license [2]”. You can’t offer a copyright license for something that
isn’t copyrighted, and the goal of CC0 is to stop things from being
copyrighted.

Additionally, saying that a work is available under “a CC0 v1.0 license”
can potentially change the (perceived) legal effect of CC0. While CC0
tries to make works no longer copyrighted, some jurisdictions don’t
allow copyright owners to do so [3]. As a result, CC0 contains (in
section 3) a fallback license. If a work remains copyrighted after CC0’s
attempt to waive copyright, then the fallback license takes effect. I’m
aware of at least one situation where someone wrote “licensed under CC0”
and meant “available under the fallback license” rather than “dedicated
to the public domain” [4].

The filename “COPYING.txt” was used because that’s the filename that
Creative Commons recommends when using CC0 on software [5].

[1]: <https://creativecommons.org/faq/#how-do-cc-licenses-operate>
[2]: <https://www.legalzoom.com/articles/what-is-a-copyright-license>
[3]: <https://wiki.creativecommons.org/images/6/69/CC0_Jurisdiction_Survey.pdf>
[4]: <https://comment.ctrl.blog/discussion/creative-commons-unicode-fallback-font>
[5]: <https://wiki.creativecommons.org/wiki/CC0_FAQ#May_I_apply_CC0_to_computer_software.3F_If_so.2C_is_there_a_recommended_implementation.3F>

README.md

@@ -104,9 +104,9 @@ this larger namespace.  But, we don't want to be so general that the spec become
 <br><br>
 
 
-## License
+## Copying information
 
-The "podcast" namespace is in the public domain under a CC0 v1.0 [license](LICENSE.txt) so as to remove all barriers to adoption, development and contribution.
+The "podcast" namespace is [dedicated to the public domain using CC0 v1.0](COPYING.txt) so as to remove all barriers to adoption, development and contribution.
 
 
 <br><br>