Rest of the _meta.app_cache stuff. Schema tests work now.

tests/app_cache/models.py

@@ -0,0 +1,17 @@
+from django.db import models
+from django.db.models.loading import BaseAppCache
+
+# We're testing app cache presence on load, so this is handy.
+
+new_app_cache = BaseAppCache()
+
+
+class TotallyNormal(models.Model):
+    name = models.CharField(max_length=255)
+
+
+class SoAlternative(models.Model):
+    name = models.CharField(max_length=255)
+
+    class Meta:
+        app_cache = new_app_cache