add redis cache, Acquisition & django-esi

api/models.py

@@ -1,2 +1,15 @@
+from django.db import models
+from sde.models import SDEType
 
-# models
+
+class Acquisition(models.Model):
+    type = models.ForeignKey(SDEType, related_name="acquisitions", on_delete=models.CASCADE)
+
+    quantity = models.IntegerField()
+    remaining = models.IntegerField()
+
+    price = models.FloatField()
+    date = models.DateTimeField(auto_now_add=True)
+    source = models.CharField(max_length=255)
+
+    user = models.ForeignKey("auth.User", related_name="acquisitions", on_delete=models.CASCADE)