dictionary-eu@4.0.0 license notice

The upstream package README states:

Dictionary and affix file: GPL-2.0.
Rest: MIT (c) Titus Wormer.

Only `index.aff` and `index.dic` are vendored in this directory, so the
dictionary and affix files are licensed under the GNU General Public License
version 2.

Source package: https://www.npmjs.com/package/dictionary-eu/v/4.0.0
Upstream source: http://xuxen.eus/eu/home
GPL-2.0 text: https://www.gnu.org/licenses/old-licenses/gpl-2.0.html