Update license banners

[Comandeer]

What is the purpose of this pull request?

Task

Does your PR contain necessary tests?

All patches that change the editor code must include tests. You can always read more
on PR testing,
how to set the testing environment and
how to create tests
in the official CKEditor documentation.

This PR contains

• Unit tests
• Manual tests

Did you follow the CKEditor 4 code style guide?

Your code should follow the guidelines from the CKEditor 4 code style guide which helps keep the entire codebase consistent.

• PR is consistent with the code style guide

What is the proposed changelog entry for this pull request?

skip

What changes did you make?

The PR contains updates of license banners in all files.

[Comandeer]

I've updated the license update script to ignore git ignored files and files inside git submodules. It's helpful when running the script in other repos, e.g. ckeditor4-docs.

I've also added a simple console.log() to know which files are touched.

[sculpt0r]

Overall looks good. However, I found a few places that should be updated. The date was updated, but due to links - they don't match to old company regexp:

Due to ☝️ maybe we can just update them manually without updating the regexp? Since tif we are going to ever change the company name again - it will be a different regexp anyway.

[Comandeer]

maybe we can just update them manually without updating the regexp?

Never! I've updated the regex accordingly 😛I've also added .json files to files allowed to be updated.

[sculpt0r]

LGTM 🎉

The RegExp looks charming... But I guess that's the nature of RegExp's :D