[admin] Use raw ids where possible and simplify scrobble inlines

vrobbler/apps/people/admin.py

@@ -6,6 +6,7 @@ from people.models import Person, PersonScrobble
 class PersonAdmin(admin.ModelAdmin):
     date_hierarchy = "created"
     list_display = ("name", "bgg_username", "bgstats_id")
+    raw_id_fields = ("user", "created_by")
     ordering = ("-created",)
     search_fields = ("name",)