Modified the admin model for SlideSubmission to use a couple of raw_id_field widgets. Commit ready for merge.

 - Legacy-Id: 16103

Author: rjsparks

ietf/meeting/admin.py

@@ -133,4 +133,6 @@ class ImportantDateAdmin(admin.ModelAdmin):
 class SlideSubmissionAdmin(admin.ModelAdmin):
     model = SlideSubmission
     list_display = ['session', 'submitter', 'title']
+    raw_id_fields = ['submitter', 'session']
+
 admin.site.register(SlideSubmission, SlideSubmissionAdmin)