Handle scenario existing file but empty

[goldyfruit]

The installer should check if the scenario file contains YAML data as for now an empty scenario file triggers the ovos-installer to run non-interactive.

[suvanbanerjee]

@goldyfruit Can i work on this issue ?

I am thinking to create a validate.sh file that will use regex to validate the correctness of config.yaml

[goldyfruit]

I am thinking to create a validate.sh file that will use regex to validate the correctness of config.yaml

No need to add complexity, the scenario logic is already there, just few missing things.
Have a look to the draft #73, still have to fix the BATS testing.