suppress some useless info from some commonly logged errors

lib/api.js

@@ -14,6 +14,7 @@ module.exports.create = function (config) {
         var special_errors = {};
         ['EPIPE', 'ECONNRESET'].forEach(function (k) { special_errors[k] = noop; });
         special_errors.NF_ENOENT = function (error, label, info) {
+            delete info.stack;
             log.error(label, {
                 info: info,
             });
@@ -27,10 +28,11 @@ module.exports.create = function (config) {
             .on('sessionClose', historyKeeper.sessionClose)
             .on('error', function (error, label, info) {
                 if (!error) { return; }
-                if (error && error.code) {
+                var code = error && (error.code || error.message);
+                if (code) {
                     /*  EPIPE,ECONNERESET, NF_ENOENT */
-                    if (typeof(special_errors[error.code]) === 'function') {
-                        return void special_errors[error.code](error, label, info);
+                    if (typeof(special_errors[code]) === 'function') {
+                        return void special_errors[code](error, label, info);
                     }
                 }