reordered access of options in tooltip and popover

Reordered access of options in tooltip and popover to allow overriding data attrs from js.

The current functionality gives higher precedence to the html, so that a call like 
```js
$('#pop').popover({content:'overriding content'})
```
does not override the html attribute 'data-content' in

```html
<div id="pop" class="btn" data-content="content" rel="popover">Button</div>
```