Consistently use userSurveys.currentPath for survey arguments
Consistently use userSurveys.currentPath for survey arguments

In both email and url type surveys we send a reference to the current page
to the survey mechanism.  As a form param for email and a query string
param for url.  If we use userSurvey.currentPath() for both it's clearer
what the intention is and more consistent.

alphagov/static,alphagov/static,alphagov/static