Extracted document filesystem serving into a separate app, see docs/Changelog.txt to update database accordingly

apps/filesystem_serving/admin.py

@@ -0,0 +1,10 @@
+from django.contrib import admin
+
+from models import DocumentMetadataIndex
+
+class DocumentMetadataIndexInline(admin.StackedInline):
+    model = DocumentMetadataIndex
+    extra = 1
+    classes = ('collapse-open',)
+    allow_add = True
+    readonly_fields = ('suffix', 'metadata_index', 'filename')