#14 enabled new annotations

Due to issue with opening annotation files with "-" in the name, this doesn't quite work.

cellxgene_gateway/flask_util.py

@@ -0,0 +1,5 @@
+from flask import request
+
+def querystring():
+    qs = request.query_string.decode()
+    return f'?{qs}' if len(qs) > 0 else ''