Can not reactivate a deleted dataset from the UI

To delete a dataset you need to go the edit form and click on the lower left red button.

After deleting the dataset, if you return to the form to reactivate it the same "Delete" button is shown and there is no "state" field that can be used to set it to active again, so effectively you can't reactivate a deleted dataset.

![CKAN master](https://f.cloud.github.com/assets/200230/248540/0e80d572-8b14-11e2-9d27-7e92611e3137.png)