Insufficient role exception should have user friendly error message

Failed to get a response! { "request": { "mbean": "io.fabric8.insight:type=LogQuery", "arguments": [ "{\"afterTimestamp\":1436886542759,\"count\":20}" ], "type": "exec", "operation": "jsonQueryLogResults" }, "stacktrace": "java.lang.Exception: Insufficient roles/credentials for operation\n\tat org.jolokia.http.HttpRequestHandler.executeRequest(HttpRequestHandler.java:214)\n\tat org.jolokia.http.HttpRequestHandler.handlePostRequest(HttpRequestHandler.java:131)\n\tat org.jolokia.http.AgentServlet$3.handleRequest(AgentServlet.java:425)\n\tat org.jolokia.http.AgentServlet.handleSecurely(AgentServlet.java:320)\n\tat org.jolokia.http.AgentServlet.handle(AgentServlet.java:291)\n\tat org.jolokia.http.AgentServlet.doPost(AgentServlet.java:259)\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:595)\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:668)\n\tat org.eclipse.jetty.servlet.ServletHolder.handle(ServletHolder.java:684)\n\tat org.eclipse.jetty.servlet.ServletHandler$CachedChain.doFilter(ServletHandler.java:1496)\n\tat io.hawt.web.AuthenticationFilter$2.run(AuthenticationFilter.java:166)\n\tat java.security.AccessController.doPrivileged(Native Method)\n\tat javax.security.auth.Subject.doAs(Subject.java:422)\n\tat io.hawt.web.AuthenticationFilter.executeAs(AuthenticationFilter.java:163)\n\tat io.hawt.web.AuthenticationFilter.doFilter(AuthenticationFilter.java:13g