Add: Auto display if error occurs option

src/Console/Console.es6

@@ -139,6 +139,12 @@ export default class Console extends Tool
         {
             parent.get('sources').set('json', data);
             parent.showTool('sources');
+        }).on('insert', (log) =>
+        {
+            if (log.type === 'error' && this.config.get('displayIfErr'))
+            {
+                parent.show().showTool('console');
+            }
         });
     }
     _hideInput()
@@ -165,7 +171,8 @@ export default class Console extends Tool
 
         cfg.set(util.defaults(cfg.get(), {
             catchGlobalErr: true,
-            overrideConsole: true
+            overrideConsole: true,
+            displayIfErr: false
         }));
 
         if (cfg.get('catchGlobalErr')) this.catchGlobalErr();

src/Console/Log.es6

@@ -195,6 +195,8 @@ export default class Log extends util.Emitter
             this._lastLog = log;
         }
 
+        this.emit('insert', log);
+
         this._isUpdated = true;
         return this.render();
     }
@@ -276,7 +278,7 @@ var evalJs = jsInput => eval.call(window, jsInput);
 function errToStr(err)
 {
     var lines = err.stack.split('\n'),
-        msg = `${lines[0]}<br/>`,
+        msg = `${err.message || lines[0]}<br/>`,
         stack = `<div class="eruda-stack">${lines.slice(1).join('<br/>')}</div>`;
 
     return msg + stack.replace(regJsUrl, match => `<a href="${match}" target="_blank">${match}</a>`);