Support for changelog and .changes file generation

Hello,
This pull request aims at creating a *.changes* file associated to the debian package, which is necessary to upload the package on a mirror. So I added a **changelog** key and a **genChanges** task.
It was necessary to make minor modifications to the **packageBin** task to conform to debian standards (especially the name of the package).
Unfortunately I could not figure out how to run the tests, so I hope I did not introduce any regression.