Thanks David Millington for pointing me to How to move your Google Code project to GitHub.
A small quote from it:
By the end of this article, you will have:
- Moved the repository, including commit history, from the Google Code project to a new GitHub project
- Updated the Google Code project to redirect to the new project location
- Updated the Google Code repository so users updating will find out they need to use the new project location
- Set up some basic project settings in your new GitHub project.
–jeroen