Remove outdated google-analytics-rails gems

It’s easier to maintain a single partial with example snippet of code than to fork, update & maintain a gem that we use none of the features of.
Extract structure for modal dialogs into helper

Convert report and claim certificate modals to use it.
Put separator line between badge and certificate embed options
Line up headings on embed modal
Convert embed modal to use helper for popup
Convert start questionnaire modal to use helper
Convert save and finish modal to helper
Create a dummy ga() function when analytics isn’t enabled
Track show/hide of modal-wide popups.

Send events to GA when full screen modal popups are shown or dismissed so that we can see if people are using them or abandoning them.
remove debug logging line
Track toggling of advanced search options

Send to GA so that we know if anyone is using it
Track showing of questionnaire sections.
Merge pull request #966 from theodi/feature-google-analytics-event-tracking

Google analytics event tracking