Please add description of how to call the tabs in the documentation

Hi, for those of us who are non programmers, it would be helpful to add a couple of examples of how to call the taxnav_display_tabs() function in themes. I believe it currently just says something like "you have to call taxnav_display_tabs(); from your theme.

For example, in the Xtemplate theme, it took me awhile to figure out the correct position and syntax for this:

//Under the line:  
print $this->template->text("header");
//Insert:
	  taxnav_display_tabs();
           print taxnav_display_tabs(); 
//this should follow: 
                    }