public function border($top, $right = null, $bottom = null, $left = null)
    {
        return $this->addItem('border', implode(',', func_get_args()));
    }
public function border($top, $right = null, $bottom = null, $left = null)
    {
        return $this->addItem('border', implode(',', func_get_args()));
    }
public function border ( $ top , $ right = null , $ bottom = null , $ left = null ) { return $ this -> addItem ( 'border' , implode ( ',' , func_get_args ( ) ) ) ; }
Applies a border to the image.

Use <b>color()</b> to specify the color of the border.

Parameters behave like CSS border sizes, the number of given
parameters modifies the function behaviour.

<li>If 1 parameter is given, all borders have the same size.
<li>If 2 parameters are given, the parameters are interpreted as vertical and
horizontal borders.
<li>If 3 parameters are given, the parameters are interpreted as top,
vertical and bottom borders.
<li>If 4 parameters are given, all borders have their respective sizes.

@param int $top    All/vertical/top border size
@param int $right  Horizontal/right border size
@param int $bottom Bottom border size
@param int $left   Left border size

@return \self
Applies a border to the image .