Don't delete the actual index definitions

mayan/apps/document_indexing/tools.py

@@ -10,9 +10,6 @@ def do_rebuild_all_indexes():
     for instance_node in IndexInstanceNode.objects.all():
         instance_node.delete()
 
-    for index in Index.objects.all():
-        index.delete()
-
     for document in Document.objects.all():
         # TODO: Launch all concurrently as background tasks
         index_document(document)