fix(tabset): preserve tabset class attribute

src/tabs/tabs.js

@@ -79,6 +79,7 @@ function TabsetCtrl($scope, $element) {
     controller: 'TabsetController',
     templateUrl: 'template/tabs/tabset.html',
     link: function(scope, element, attrs) {
+      scope.class = angular.isDefined(attrs.class) ? attrs.class : '';
       scope.vertical = angular.isDefined(attrs.vertical) ? scope.$eval(attrs.vertical) : false;
       scope.type = angular.isDefined(attrs.type) ? scope.$parent.$eval(attrs.type) : 'tabs';
     }

src/tabs/test/tabsSpec.js

@@ -460,6 +460,19 @@ describe('tabs', function() {
     });
   });
 
+  describe('class', function() {
+    beforeEach(inject(function($compile, $rootScope) {
+    scope = $rootScope.$new();
+
+    elm = $compile('<tabset class="tabs-left"></tabset>')(scope);
+    scope.$apply();
+    }));
+
+    it('to stack tabs', function() {
+      expect(elm.find('div.tabbable')).toHaveClass('tabs-left');
+    });
+  });
+
   describe('type', function() {
     beforeEach(inject(function($compile, $rootScope) {
       scope = $rootScope.$new();

template/tabs/tabset.html

@@ -1,5 +1,5 @@
 
-<div class="tabbable">
+<div class="tabbable {{class}}">
   <ul class="nav {{type && 'nav-' + type}}" ng-class="{'nav-stacked': vertical}" ng-transclude>
   </ul>
   <div class="tab-content">