Refresh stats once inaccurate data fixed

[iandunn]

Most of the changes in #83 are done, but the stats are still very distorted by cases where people confused writing their own themes with contributing to the Theme Review team, etc. There's no good way for us to detect and automatically fix that, so I think we should email everyone after #83 and #119 are done, and ask them to update their data to be accurate.

#119 is still in progress, though. There's also #124 and #125.

#81 was merged to track stats, and the drafted page is at https://wordpress.org/five-for-the-future/?page_id=684&preview=true. We can complete and merge #38 (visualizations), but I think we should wait to publish the page until the data is more accurate.

Otherwise, the report will show all of the stats dropping significantly as people correct their inaccurate data. Visitors would interpret that as the program being unsuccessful, when in reality we're just calibrating after the launch.

I think we'll likely need to just delete the old snapshots, and start recording only after the data is reasonably accurate. It'll never be 100% of course, and that's fine, as long as it's close enough to be in the ballpark of reality.

[iandunn]

Dependent on #121