Contributing a File Content Type to Eclipse

While using Papyrus, I found an error about its Refactoring process, and I solved this problem.

Papyrus doesn't provide any content type for '.di' file and '.notation' file.

That result in the exclusion of '.di' and '.notation' from the refactoring target.

Contributing file content type for those like below blew away that problem.

The whole problem and solution are in this link.

http://www.eclipse.org/forums/index.php/t/461179/