updated description on enumconverter, enumsetconverter, regexpatternconverter, iso*date and iso*calendar converters, subjectconverter and charsetconverter
updated description on enumconverter, enumsetconverter, regexpatternconverter, iso*date and iso*calendar converters, subjectconverter and charsetconverter

8nevil8/xstream,hudson/xstream