Accept int as map key too

Accept integers in severity map too since when you pass the following

    "text": {
            "type": "text",
            "include": "(\\.*)",
            "severity": {
                "3": "advice"
            }
        },

to `.arclint` it throws an error. Reason is `json_decode` or PHP itself implicitly casting `"3"` into an integer `3`.