Merge pull request #131 from lexifdev/master

Add "on_delete" for Korean version.

Author: das-g

ko/homework_create_more_models/README.md

@@ -8,7 +8,7 @@
 
 ```python
 class Comment(models.Model):
-    post = models.ForeignKey('blog.Post', related_name='comments')
+    post = models.ForeignKey('blog.Post', on_delete=models.CASCADE, related_name='comments')
     author = models.CharField(max_length=200)
     text = models.TextField()
     created_date = models.DateTimeField(default=timezone.now)