1.9 has been out of β for some time; clean up deprecation warnings

I'm kind of surprised that `on_delete` is going to become
mandatory. Is it that explicit is better than ...?

core/models.py

@@ -21,7 +21,7 @@ def karma(self):
 
 
 class Post(models.Model, VotableMixin):
-    author = models.ForeignKey("FinetoothUser")
+    author = models.ForeignKey("FinetoothUser", on_delete=models.CASCADE)
     title = models.CharField(max_length=200)
     content = models.TextField(
         validators=[
@@ -55,10 +55,10 @@ class Meta:
 
 
 class Comment(models.Model, VotableMixin):
-    commenter = models.ForeignKey("FinetoothUser")
+    commenter = models.ForeignKey("FinetoothUser", on_delete=models.CASCADE)
     content = models.TextField()
-    post = models.ForeignKey("Post")
-    parent = models.ForeignKey("Comment", null=True)
+    post = models.ForeignKey("Post", on_delete=models.CASCADE)
+    parent = models.ForeignKey("Comment", null=True, on_delete=models.CASCADE)
     published_at = models.DateTimeField(auto_now_add=True)
 
     def __str__(self):
@@ -83,19 +83,19 @@ def vote_set(self):
 
 
 class Vote(models.Model):
-    voter = models.ForeignKey("FinetoothUser")
+    voter = models.ForeignKey("FinetoothUser", on_delete=models.CASCADE)
     value = models.IntegerField()
     start_index = models.PositiveIntegerField()
     end_index = models.PositiveIntegerField()
 
 class PostVote(Vote):
-    post = models.ForeignKey("Post")
+    post = models.ForeignKey("Post", on_delete=models.CASCADE)
 
     def __str__(self):
         return "{} on post #{}".format(self.value, self.post.pk)
 
 class CommentVote(Vote):
-    comment = models.ForeignKey("Comment")
+    comment = models.ForeignKey("Comment", on_delete=models.CASCADE)
 
     def __str__(self):
         return "{} on comment #{}".format(self.value, self.comment.pk)

dev_requirements.txt

@@ -1,7 +1,7 @@
 bleach==1.4.1
-Django==1.9b1
+Django==1.9.1
 django-debug-toolbar==1.3
-django-extensions==1.5.5
+django-extensions==1.6.1
 ipython==3.1.0
 Markdown==2.6.1
 jasmine==2.0.1

requirements.txt

@@ -1,9 +1,9 @@
 bleach==1.4
-Django==1.8
+Django==1.9.1
 Markdown==2.4.1
 dj-database-url==0.3.0
 dj-static==0.0.6
-django-extensions==1.5.5
+django-extensions==1.6.1
 gunicorn==19.1.1
 ipython==3.1.0
 psycopg2==2.5.1

settings.py

@@ -45,6 +45,7 @@
 
 MIDDLEWARE_CLASSES = (
     'django.contrib.sessions.middleware.SessionMiddleware',
+    'django.contrib.auth.middleware.SessionAuthenticationMiddleware',
     'django.middleware.locale.LocaleMiddleware',
     'django.middleware.common.CommonMiddleware',
     'django.middleware.csrf.CsrfViewMiddleware',