Didn't notice it because vendor/ was already populated on my dev
machine, but did notice it in Docker build.
Docker build now consumes devsetup like regular user, so this should
catch future problems.
Remove remaining curl|shit functionality from lazy.sh (no checkout logic
needed anymore).
refs #35
Version is autodetected on build using git
If it cannot be detected with git, an override must be provided.
For tracability of distros, the distroy packagers should override as
well, which is why I added a README entry for package mainatiners.
refs #35
