Set the Hostname in the VM

GitLab automatically takes the hostname and infers the external URL from it. This makes it convenient to be able to give the host a specific name by which it is then accessed.

The internal network that the Virtual Machine Manager is running will also route DNS queries based on these. So if you started a box called primary and another called secondary they would be able to use this as a domain name and ping or curl each other on that name.

I also add a few VMware settings and made both VMware and Virtualbox a linked_clone which makes things start up noticably faster while using less disk space. The only downside here is that deleting the base box in ~/.vagrant.d renders the VM completely unusable and it needs to be built from scratch. I think this is a good tradeoff for a testing environment.