Initial sketch of bug #282, aggregate cell data export.

I believe this mostly accomplishes the "hourly exports of changes to Cell table" issue, in very broad brush strokes. I haven't managed to test it against S3 live yet and I expect the fields will change some and possibly need preprocessing before export, but I'm posting this for feedback / review now.
The one in the backup module involves a directory-within-a-directory that is then zipped (like into a .zip file). This one is a single dir that holds a .gz file we're writing. They are a bit different.

Similarly the GzipFile adaptor isn't required in the backup routine because it uses a .zip file. I could try to consolidate the strategies if you like, or use a .zip file for publishing our exports as well.