license clarification

[ghost]

Would be nice to add SPDX tags - see https://spdx.org/licenses/ to make it easier to discover the code license using automated tools. On a related note - having COPYING file in a project's root would allow github to automatically recognize the code license.

Keep up the good work!

[MatiasVara]

Hello Osmoc and thanks for your comment. I add the text of the license to the root.