Some fixes to the latest updates (#18)

This PR contains the work done to:
* update the header files of all the existing source files in the project with the Apache License;
* update the main article of the `DocC` documentation catalog;
* update the `README` file;
* regenerate the Github Pages documentation from the `DocC` documentation catalog.

Reviewed-on: #18
Co-authored-by: Javier Cicchelli <javier@rock-n-code.com>
Co-committed-by: Javier Cicchelli <javier@rock-n-code.com>

docs/data/documentation/amiiboservice/amiibo/release-swift.struct/japan.json

@@ -1 +1 @@
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