Allow cross domain XHR calls

beforeIntercept.groovy

    def beforeInterceptor = { model ->
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "GET,OPTIONS");
        response.setHeader("Access-Control-Allow-Headers", "Content-Type");
        response.setHeader("Access-Control-Allow-Credentials", "false");
        response.setHeader("Access-Control-Max-Age", "60");
        response.setHeader("Content-Type","text/xml")
    }