[PATCH] models: Make series.project nullable

[Stephen Finucane]

This is reflected in the migration but not the model.

Signed-off-by: Stephen Finucane <stephen at that.guru>
Fixes: c1d8a0d ("Fix series.project migration logic")
Cc: Andy Doan <andy.doan at linaro.org>
---
 patchwork/models.py | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/patchwork/models.py b/patchwork/models.py
index d698e23..cf363f0 100644
--- a/patchwork/models.py
+++ b/patchwork/models.py
@@ -551,7 +551,8 @@ class Series(models.Model):
     """An collection of patches."""
 
     # parent
-    project = models.ForeignKey(Project, related_name='series')
+    project = models.ForeignKey(Project, related_name='series', null=True,
+                                blank=True)
 
     # content
     cover_letter = models.ForeignKey(CoverLetter,
-- 
2.9.3