Google Analytics tracking for resource download dropoffs

[bennylope]

The goal is to develop analytics data around resource access, specifically to allow the team to identify where users are dropping off from downloading resources.

The implementation will involve adding event tracking to the resource access/download flow, including resource page access, clicking on resource links (file/shared URL) on the page, and the registration pages.

Naming scheme examples include category or categories resource and possibly registration, and actions including viewed, cancelled, submitted.

[bennylope]

@paultuthill Here's the issue in question