You may use this project under the terms of either the MIT License or the GNU General Public License (GPL) Version 2. You don’t need to do anything special in order to choose one of these licenses nor do you need to notify anyone. You are free to use this project in a commercial project as long as the copyright header is left intact.
The MIT license is recommended for most projects. It is simple and easy to understand, it places almost no restrictions on what you can do with this project. More information about this license can be found on its Wikipedia page.
If the GPL license is a better fit, you are also free to use the project under that license. More information about this license can be found on its Wikipedia page.