change Namecheap trigger to 'startend' type

Also, the UI changes already work:

Unavailable
![selection_260](https://cloud.githubusercontent.com/assets/94489/5495070/f9bfde22-86bf-11e4-9b69-b2dea5b255d0.png)

Available
![selection_261](https://cloud.githubusercontent.com/assets/94489/5495081/0d5b7d6a-86c0-11e4-9d74-6bdbcafc0979.png)