migrate answers example from yaml to json

[jreidinger]

Problem

When changing answers format from yaml to json example file was not converted.

Solution

Convert it and also use example which provides password.

[mvidner]

May I suggest a reformatted version (via python -m json.tool)

{
    "answers": [
        {
            "answer": "decrypt",
            "class": "storage.luks_activation",
            "password": "my_password"
        }
    ]
}