Add labels to the masscan VM

[djaara]

Create VM with labels:

• owner to identify who owns the VM and who should be notified if it is left behind
• delete_after to know the expected lifespan of the VM, when it can be safely deleted

[bobek]

Thank you for the proposal. I like the idea for setting the labels, but we need to find the way how to make it more generic. E.g. via adding options or environment variables. Similarly to #4 .