added manual refresh functionality, fixed mistake with meaning of File directory field (foreign key not path)

viewer/migrations/0005_serveddirectory_known_subdirectories.py

@@ -0,0 +1,19 @@
+# Generated by Django 3.1.2 on 2020-11-01 01:46
+
+from django.db import migrations
+import jsonfield.fields
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('viewer', '0004_file'),
+    ]
+
+    operations = [
+        migrations.AddField(
+            model_name='serveddirectory',
+            name='known_subdirectories',
+            field=jsonfield.fields.JSONField(default=[], verbose_name='Tracked Subdirectories JSON'),
+        ),
+    ]