Debian packaging

Maven needs to download dependencies which Launchpad doesn't allow.
So for a PPA build you need to add a pre-compiled jar file.
Put it in the top directory and rename it to dualsub.jar. Then build a source package with `debuild -S -sa`

Then the PPA build will work: https://launchpad.net/~djcj/+archive/ubuntu/dualsub-test/+packages