Offer the option to automatically delete HTML comments from page

Making a pull request for posterity.

Sample graphics:

* what one sees if there are long html comments on the page:
![screen shot 2013-09-17 at 8 33 23 pm](https://f.cloud.github.com/assets/1410202/1162096/7e7e9cbe-2002-11e3-850b-6440011174e9.png)

* if you click on a "delete comment" link (after the "Comment removed" text displays for a second, it disappears):
![screen shot 2013-09-17 at 8 33 56 pm](https://f.cloud.github.com/assets/1410202/1162097/8b8a8878-2002-11e3-8449-a394914eaead.png)

* and if you delete all the html comments, then the long comment notice automagically disappears (yay!):
![screen shot 2013-09-17 at 8 34 08 pm](https://f.cloud.github.com/assets/1410202/1162100/a93a64ba-2002-11e3-9171-bdf92308546b.png)