[support] over-riding Garland's list item bullet points.

[J-P Stacey]

> <ul style="background-image:none;list-style-type:none;">
>    <li style="background-image:none;list-style-type:none;">Apples</li>
>    <li style="background-image:none;list-style-type:none;">Bananas</li>
>    <li style="background-image:none;list-style-type:none;">Pears</li>
> </ul>
> 
> and the white graphical discs remain steadfastly. 

Not considering the inline/cacheing problem that seems to have been solved 
elsewhere, I needed ID specifiers to get this to work:

#header #nav-primary li {
         list-style-type: none;
         background-image: none;
}

This is probably because the existing Garland CSS statement

ul li, ul.menu li, .item-list ul li, li.leaf {
	background: transparent url(images/menu-leaf.gif)
		no-repeat scroll 1px 0.35em;
	/* ... */
}

typically has two tag specifiers and a classname specifier, so you need 
either 2+ classnames or an ID to beat that.

<http://www.w3.org/TR/REC-CSS2/cascade.html#specificity> should help, 
although it doesn't make any explicit statement on the super-specificity of 
inline styles that I can see.

Cheers,
J-P