Generate distributional data not averages.

Value-counts can be summed out, totalled and averaged so is generally
more useful that a precalculated summary statistic like average.
Move analytics calculations entirely porter side.
Zone UK is now called UK News in CSS
Change irrelevant comment
Merge pull request #1214 from guardian/cricket

Fix typo for a tag in cricket articles
Merge pull request #1212 from guardian/kpis

Move analytics calculations entirely porter side.
Fix path to cricket match card in sport healthcheck.
Add analytics for weekly and monthly pageviews and days seen per user.
Merge pull request #1217 from guardian/kpis

Add analytics for weekly and monthly pageviews and days seen per user.
Merge pull request #1213 from guardian/zone-uk-news

Zone UK is now called UK News in CSS
Add scorecard table headers

Minor styling tweaks, bold inline names, and reword headings.