removed start/end dates from mobile charts

app/views/dashboard/link-analyzer.pug

@@ -15,7 +15,7 @@ block content
 
           canvas(id="link-visits").visit-graph
 
-          div(uk-grid).uk-flex-between.uk-text-small
+          div(class="uk-visible@m", uk-grid).uk-flex-between.uk-text-small
             .uk-width-auto
               .uk-margin
                 div= moment(linkVisitStats.start).format('MMM DD, YYYY h:mm:ss a')

app/views/dashboard/view.pug

@@ -18,7 +18,7 @@ block content
             .uk-card.uk-card-secondary.uk-card-small.uk-card-body
               h4.uk-card-title Link Visits #[small.uk-text-muted past 7 days]
               canvas(id="profile-stats").visit-graph
-              div(uk-grid).uk-flex-between.uk-text-small
+              div(class="uk-visible@m", uk-grid).uk-flex-between.uk-text-small
                 .uk-width-auto
                   .uk-margin
                     div= moment(userVisitStats.start).format('MMM DD, YYYY h:mm:ss a')