Add preliminary report system

The report system is pretty low-tech. However the scaffolding is there
for a lot of new stuff. What we currently have:

* Users can create reports
* Staff can view reports
* Admins can create report templates

There's a post drop-down menu available on all posts now, too. This is
where "report post" menu item lives and other things like that can be
added too.

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

board/forms.py

@@ -1,6 +1,6 @@
 from django.conf import settings
 from django.forms import ModelForm
-from board.models import Post
+from board.models import Post, Report
 from hcaptcha.fields import hCaptchaField
 
 
@@ -41,3 +41,20 @@ class ReplyForm(PostForm):
         super(ReplyForm, self).__init__(*args, **kwargs)
         self.instance.op = op
         self.instance.reply = reply
+
+
+class ReportForm(ModelForm):
+    """
+    A form used to create reports on posts.
+
+    This requires the board and the IP address to be specified.
+    """
+
+    class Meta:
+        model = Report
+        fields = ["reason"]
+
+    def __init__(self, *args, op, board, ip, **kwargs):
+        super(ReportForm, self).__init__(*args, **kwargs)
+        self.instance.ip = ip
+        self.instance.post = op