Ahoy integration updates

Ahoy in Admin - links in top_bar
views in ahoy_views 
table in ahoy event & ahoy visits - users behaviour
track taxon concept index&show - added ahoy_tracking to api/taxon concept controller
changes to what is being track - edit track show
not sure about this file -- looks like a copy of app/views/admin/exports/index.html.erb, do we need this?