VirtualBox Headless mode

I use VirtualBox and do some testing and learning with multiple machines running at once.

Usually those machines are servers so I don't really need the GUI since I connecting to them using SSH clinet.

When VirtualBox is installed you'll see `VBoxManage` executable (`vboxmanage` is also there as alias) which is CLI tool that allows you to interact with your VMs.

Here is a command how you can start VM in headless mode:

To shutdown the VM run this:

Have fun.