Resolves #3 — start_time, end_time, and limit can now be blank. Tests already dealt with the null case.

registrasion/migrations/0010_auto_20160330_2342.py

@@ -0,0 +1,29 @@
+# -*- coding: utf-8 -*-
+from __future__ import unicode_literals
+
+from django.db import migrations, models
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('registrasion', '0009_auto_20160330_2336'),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name='timeorstocklimitenablingcondition',
+            name='end_time',
+            field=models.DateTimeField(help_text='Products included in this condition will only be available before this time.', null=True, blank=True),
+        ),
+        migrations.AlterField(
+            model_name='timeorstocklimitenablingcondition',
+            name='limit',
+            field=models.PositiveIntegerField(help_text='The number of items under this grouping that can be purchased.', null=True, blank=True),
+        ),
+        migrations.AlterField(
+            model_name='timeorstocklimitenablingcondition',
+            name='start_time',
+            field=models.DateTimeField(help_text='Products included in this condition will only be available after this time.', null=True, blank=True),
+        ),
+    ]

registrasion/models.py

@@ -441,16 +441,19 @@ class TimeOrStockLimitEnablingCondition(EnablingConditionBase):
 
     start_time = models.DateTimeField(
         null=True,
+        blank=True,
         help_text=_("Products included in this condition will only be "
                     "available after this time."),
     )
     end_time = models.DateTimeField(
         null=True,
+        blank=True,
         help_text=_("Products included in this condition will only be "
                     "available before this time."),
     )
     limit = models.PositiveIntegerField(
         null=True,
+        blank=True,
         help_text=_("The number of items under this grouping that can be "
                     "purchased."),
     )