license: remove CMB-isms to become 3-clause BSD
Following a9ebd32b (A new cmb6 branded app), the README file was updated to mention the project is licensed under "OSI-approved BSD 3-clause License" but the "License.txt" is not the official text and this causes the license parser to improperly identify the license.
Topic-rename: license-remove-cmbisms
Edited by Ben Boeckel