Adapted to the MIT license migration of the main "Nord" (1) project.
Detailed information can be found in the main task ticket.

All license SVG badges and the "LICENSE.md" content have been updated.
In addition all source code comment header have also been simplified.

References:

* (1) https://github.com/arcticicestudio/nord

Subtask of nordtheme/nord#55
GH-16

…mit-license

Migrate to MIT license

As part of the "Northern Post - The state and roadmap of Nord" [1]
announcement, this repository will be migrated to the `nordtheme` GitHub
organization [2].
This issue is a task of the nordtheme/nord#185 [3] epic (tasklist [4]).

[1]: https://github.com/orgs/nordtheme/discussions/183
[2]: https://github.com/nordtheme
[3]: nordtheme/nord#185
[4]: https://docs.github.com/en/get-started/writing-on-github/working-with-advanced-formatting/about-task-lists

GH-19

With the retirement of the "Arctic Ice Studio" personal & Nord project
brand [1] various migrations to the `svengreb` GitHub account [2] of
other projects were also completed within the last weeks. There are also
changes in Nord projects like `nordtheme/web` that other projects
depended on and can now be adapted as well.
Therefore all Nord projects must adapt these changes which includes...

- the migration and repository name change of
  `arcticicestudio/nord-docs`[2] - all references must be updated.
- the migration of the `arcticicestudio/styleguide-git` repository to
  the `svengreb` "real-in-person" identity [3] - all references and
  used npm packages must be updated.
- the migration of the `arcticicestudio/styleguide-javascript`
  repository to the `svengreb` "real-in-person" identity [4] - all
  references and used npm packages must be updated.
- the migration of the `arcticicestudio/styleguide-markdown` repository
  to the `svengreb` "real-in-person" identity [5] - all references and
  used npm packages must be updated.

[1]: https://github.com/orgs/nordtheme/discussions/183#retire-arctic-ice-studio-as-nord-brand
[2]: nordtheme/web#241
[3]: svengreb/styleguide-git#12
[4]: svengreb/styleguide-javascript#88
[5]: svengreb/styleguide-markdown#63

GH-21