Make sure that the Debian package we build conforms to the expected
naming scheme else, it's possible that something is off. A scenario
we've encountered is bumping `share/version.txt`, but not
`debian/changelog`, which would create a Debian package with an older
version.
As a result, a new `debian` folder is now living in the repository.
Debian packaging is now done manually rather than using tools that do
the heavy-lifting for us.
The `build-deb.py` script has also been updated to use `dpkg-buildpackage`
Add an optional --distro argument to build-deb.py, to specify the Debian
version in the package name, which currently is "1". This option may
prove useful when publishing packages to freedomofpress/apt-tools-prod,
where packages from different distros with the same names but different
contents are not accepted.