Add core models to admin interface.

biscuit/core/admin.py

+from django.contrib import admin
+from .models import Group, Person, School, SchoolTerm
+
+
+class PersonAdmin(admin.ModelAdmin):
+    pass
+
+
+admin.site.register(Person, PersonAdmin)
+
+
+class GroupAdmin(admin.ModelAdmin):
+    pass
+
+
+admin.site.register(Group, GroupAdmin)
+
+
+class SchoolAdmin(admin.ModelAdmin):
+    pass
+
+
+admin.site.register(School, SchoolAdmin)
+
+
+class SchoolTermAdmin(admin.ModelAdmin):
+    pass
+
+
+admin.site.register(SchoolTerm, SchoolTermAdmin)