Update CHANGELOG
Update CHANGELOG

wraziens/PyMySQL,Geoion/Tornado-MySQL,NunoEdgarGub1/PyMySQL,boneyao/PyMySQL,wraziens/PyMySQL,eibanez/PyMySQL,pymysql/pymysql,anson-tang/PyMySQL,MartinThoma/PyMySQL,Ting-y/PyMySQL,mosquito/Tornado-MySQL,modulexcite/PyMySQL,yeyinzhu3211/PyMySQL,PyMySQL/PyMySQL,nju520/PyMySQL,methane/PyMySQL,lzedl/PyMySQL,xjzhou/PyMySQL,jheld/PyMySQL,jwjohns/PyMySQL,PyMySQL/Tornado-MySQL,yeyinzhu3211/PyMySQL,lzedl/PyMySQL,pulsar314/Tornado-MySQL,xjzhou/PyMySQL,eibanez/PyMySQL,DashaChuk/PyMySQL