Feature: Use char-field instead of url-field to fit strange types of url

Now Pinry will not care type of url, if it could be input, it could be
saved.
This may cause xss issue but Pinry is a private pin-board replacement,
so be it.

core/migrations/0004_auto_20190715_0912.py

@@ -0,0 +1,30 @@
+# -*- coding: utf-8 -*-
+# Generated by Django 1.11.20 on 2019-07-15 09:12
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('core', '0003_auto_20190222_1358'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='pin',
+            name='origin',
+            field=models.CharField(blank=True, max_length=256, null=True),
+        ),
+        migrations.AlterField(
+            model_name='pin',
+            name='referer',
+            field=models.CharField(blank=True, max_length=256, null=True),
+        ),
+        migrations.AlterField(
+            model_name='pin',
+            name='url',
+            field=models.CharField(blank=True, max_length=256, null=True),
+        ),
+    ]

core/models.py

@@ -72,11 +72,11 @@ class Image(BaseImage):
 
 class Pin(models.Model):
     submitter = models.ForeignKey(User)
-    url = models.URLField(null=True, blank=True)
+    url = models.CharField(null=True, blank=True, max_length=256)
     # origin is tha same as referer but not work,
     # should be removed some day
-    origin = models.URLField(null=True, blank=True)
-    referer = models.URLField(null=True, blank=True)
+    origin = models.CharField(null=True, blank=True, max_length=256)
+    referer = models.CharField(null=True, blank=True, max_length=256)
     description = models.TextField(blank=True, null=True)
     image = models.ForeignKey(Image, related_name='pin')
     published = models.DateTimeField(auto_now_add=True)