tree c33f17d168179b773fd377e9c2c1b3db39e61f1a
parent 6db61b4e523dae71e1720c2267cd6b811fa3dcf2
author Will Angley <willangley@google.com> 1426639551 -0400
committer Will Angley <willangley@google.com> 1426640372 -0400

Start using csv.writer to handle report output.

This allows us to stop using '' where we mean None at several places in
the code, since the csv.writer will translate it for us properly.

Change-Id: I075c5fa2e1ad2d5d263095c4312bed4af309ff6d