Allow action buttons in empty state for a card/list/table view

[rhwood]

Add ability to put action buttons in the empty state view for card, list, or table view.
Addresses #510.

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This change is 

[dtaylor113]

Hi, I noticed that clicking on the empty state action buttons do not update the Events textarea. i believe because the callback function for empty state actions only pass an 'action' parameter, and not an 'item' param, so you cannot reuse the existing perfromActions(actions, item) method. Please update to use a correct callback function, thanks!

[dtaylor113]

Other than the one issue I raised, LGTM!

[rhwood]

For some reason, which I can't figure out, the actionFn property is becoming undefined for the empty state buttons in any/all examples. I have examples that use a different function for the actionFn property, but when the button is clicked in a browser, that property is undefined.

[dtaylor113]

For some reason, which I can't figure out, the actionFn property is becoming undefined

Hi, you need to put the actionFn above/before the emptyStateActionButtons array/obj definition. This worked for me:

          var performEmptyStateAction = function (action) {
            $scope.eventText = action.name + " executed\r\n" + $scope.eventText;
          };

          $scope.emptyStateActionButtons = [
            {
              name: 'Main Action',
              title: 'Perform an action',
              actionFn: performEmptyStateAction,
              type: 'main'
            },

[dtaylor113]

LGTM, thanks!

[cdcabrera]

@rhwood looking good on the PR, if you can squash those commits with a rebase we'll go ahead and merge it in