This commit brings back some reports hidden or changed
by the commit in 14b436923c if
the site setting `use_legacy_pageviews` is false.
* Unhide the old “Consolidated Pageviews” report and rename it
to “Legacy Consolidated Pageviews”
* Add a legacy_page_view_total_reqs report called “Legacy Pageviews”,
which calculates pageviews in the same way the old page_view_total_reqs
report did.
This will allow admins to better compare old and new pageview
stats which are based on browser detection if they have switched
over to _not_ use legacy pageviews.
