Single attributes

A number of HTML attributes only require a name, and not a name = "value" pair. 
Notably the selected, checked and readonly tags when dealing with forms. The 
current behaviour if you set any of these is to get the following output in your
HTML <input type="text" name="txtBox" value="My Text" readonly="readonly" />. 

This appears to work, esp for the checked and selected tags of radio buttons/ 
check boxes and select options. But I don't think this is quite what was
intended.

The HTMLAttribute class does provide a constructor that accepts one parameter, 
but that parameter is mirrored to both the name and the value members. I propose 
a change as follows to the constructor

CGICCNS HTMLAttribute::HTMLAttribute(const STDNS string& name) 
  : fName(name), 
    fValue() 
{} 

and hence the render member function can be changed as follows: 
void 
CGICCNS HTMLAttribute::render(STDNS ostream& out)               const 
{ 
        if (!getValue().empty()) { 
                out << getName() << "=\"" << getValue() << "\""; 
        } 
        else { 
                out << getName(); 
        } 
} 

Which would then render the attribute as expected. 

Quintin