Merge pull request #500 from metabase/dash_borders

fix dashboard borders

resources/frontend_client/app/dashboard/partials/_card.html

-<div class="Card" ng-class="{ 'Card--errored': cardDataEmpty || cardData.error || sqlError }">
+<div class="Card bordered rounded" ng-class="{ 'Card--errored': cardDataEmpty || cardData.error || sqlError }">
     <div id="{{chartId}}_heading" ng-include="'/app/dashboard/partials/_card_heading.html'" onload="headerLoaded = true"></div>
 
     <div ng-if="cardDataEmpty && !sqlError">