Page View Tracking data should be exposed in stats

[jqnatividad]

CKAN version
2.9.1

Describe the bug
page view tracking logically falls under stats and should be exposed in /stats when both are enabled. Right now, stats doesn't use page view tracking data at all.
This is especially important in secure enterprise installations when google analytics cannot be used.

Steps to reproduce
Enable page view tracking and stats and go to /stats.

Expected behavior
When both stats and activity tracking are enabled, the following detailed statistics will also be shown in /stats.

• most_popular
• most_popular_by_week