#17 Update setup

* removes unused organisation app from project
* removes null=True parameters for M2M fields in models

codelist/models.py

@@ -76,7 +76,6 @@ class KonovaCodeList(models.Model):
     )
     codes = models.ManyToManyField(
         KonovaCode,
-        null=True,
         blank=True,
         help_text="Codes for this list",
         related_name="code_lists"