Support for x-www-form-urlencoded

[m-horky]

Input type application/x-www-form-urlencoded is not supported.

The following is an excerpt from Swagger's example API, which cannot be expressed via autocli-generated library:

{
"paths": {
    "/pet/{petId}": {
        "post": {
            "consumes": ["application/x-www-form-urlencoded"],
            "produces": ["application/json", "application/xml"],
            "parameters": [
                {
                    "name": "petId",
                    "in": "path",
                    "description": "ID of pet that needs to be updated",
                    "required": true,
                    "type": "integer",
                    "format": "int64"
                },
                {
                    "name": "name",
                    "in": "formData",
                    "description": "Updated name of the pet",
                    "required": false,
                    "type": "string"
                },
                {
                    "name": "status",
                    "in": "formData",
                    "description": "Updated status of the pet",
                    "required": false,
                    "type": "string"
                }
            ],
            "responses": {"405": {"description": "Invalid input"}},
            "security": [{"petstore_auth": ["write:pets", "read:pets"]}]
        }
    }
}

Preferable way of handling this would be adding a new flag -F.