This release changes the versioning scheme to use semantic versioning.
It is also the first release where I start to pay more attention to
everything in general.
Since we are still changing a lot of program details and functionality, we are
in an unstable state, hence the major version number being 0. We chose 3 as the
minor number because that was the next one coming.
The primary change from the previous version is improved documentation
and the use of dependency vendoring.