code: private String parseNCName() {
  
          final String ncName = mToken.getContent();
  
          consume(TokenType.TEXT, true);
  
          return ncName;
      }
docs: Parses the the rule NCName according to the following production rule:
  http://www.w3.org/TR/REC-xml-names
  <p>
  [4] NCName ::= NCNameStartChar NCNameChar*
  </p>
  <p>
  [5] NCNameChar ::= NameChar - ':'
  </p>
  <p>
  [6] NCNameStartChar ::= Letter | '_' => NCName : Token.TEXT .
  </p>
  
  @return string representation of NCName