Vagrantfile

Merged username-removed-35547 requested to merge perj/gitlab-development-kit:vagrantfile into master

I've successfully used this Vagrantfile with vagrant-lxc. It works with VirtualBox as well, but not using the shared /vagrant/ directory since PostgreSQL and redis don't want to run there (probably because mmap and/or unix sockets doen't work). Moving them out of /vagrant/ makes it work, but that's not covered here.