Export participants to different formats

* CSV
* PDF (requires Python dependency `weasyprint`)
* ODS (requires Python dependency `pyexcel_ods3`)

Signed-off-by: Thomas Citharel <tcit@tcit.fr>

priv/python/ods.py

@@ -0,0 +1,12 @@
+from pyexcel_ods3 import save_data
+from collections import OrderedDict
+from io import BytesIO as StringIO
+import json
+
+def generate(data):
+    struct = json.loads(data)
+    data = OrderedDict()
+    data.update({"Sheet 1": struct})
+    io = StringIO()
+    save_data(io, data)
+    return io.getvalue()