function SelectorSubPart(text, type, line, col){
    
    SyntaxUnit.call(this, text, line, col, Parser.SELECTOR_SUB_PART_TYPE);

    /**
     * The type of modifier.
     * @type String
     * @property type
     */
    this.type = type;
    
    /**
     * Some subparts have arguments, this represents them.
     * @type Array
     * @property args
     */
    this.args = [];

}
Represents a selector modifier string, meaning a class name, element name,
element ID, pseudo rule, etc.
@namespace parserlib.css
@class SelectorSubPart
@extends parserlib.util.SyntaxUnit
@constructor
@param {String} text The text representation of the unit. 
@param {String} type The type of selector modifier.
@param {int} line The line of text on which the unit resides.
@param {int} col The column of text on which the unit resides.