Allow writing to all of pinaxcon/site_media/media

We previously allowed writing to the `documents` sub-directory, but we also need
to write to `speaker_photos` to upload speaker photos. Simplest to allow writing
to the `media` parent directory.

fabfile.py

@@ -41,7 +41,9 @@ def deploy(c):
     df2.fix_permissions(
         c,
         read=['pinaxcon', 'vendor', 'static'],
-        read_write=[],
+        # For speaker photos and attaching supporting docs to a proposal (select
+        # "view details" after submitting).
+        read_write=['pinaxcon/site_media/media'],
     )
     df2.reload_uwsgi(c)
     df2.flush_memcached(c)