Replace <> (#260)

Author: adam-urbanczyk

cq_editor/widgets/traceback_viewer.py

@@ -67,10 +67,11 @@ def addTraceback(self,exc_info,code):
                 root.addChild(QTreeWidgetItem([el.filename,
                                                str(el.lineno),
                                                line]))
-            
+
             exc_name = t.__name__
             exc_msg = str(exc)
-            
+            exc_msg = exc_msg.replace('<', '&lt;').replace('>', '&gt;') #replace <> 
+
             self.current_exception.\
                 setText('<b>{}</b>: {}'.format(exc_name,exc_msg))