Ensure that Connection._result is initialised early
Ensure that Connection._result is initialised early

2a520f63 introduced a bug, becuase Connection.set_charset can be called
by Connection.__init__, before _result is added to the object.
Subsequent tests for _result is not None would raise an exception.

MartinThoma/PyMySQL,lzedl/PyMySQL,wraziens/PyMySQL,mosquito/CyMySQL,NunoEdgarGub1/PyMySQL,lzedl/PyMySQL,jheld/PyMySQL,methane/MyKaze,modulexcite/PyMySQL,methane/PyMySQL,anson-tang/PyMySQL,nju520/PyMySQL,shaun-jss/PyMySQL_py3k,Geoion/Tornado-MySQL,aio-libs/aiomysql,PyMySQL/PyMySQL,xjzhou/PyMySQL,nakagami/CyMySQL,xjzhou/PyMySQL,DashaChuk/PyMySQL,eibanez/PyMySQL,yeyinzhu3211/PyMySQL,mosquito/Tornado-MySQL,shaun-jss/PyMySQL_py3k,pulsar314/Tornado-MySQL,boneyao/PyMySQL,yeyinzhu3211/PyMySQL,wraziens/PyMySQL,eibanez/PyMySQL,Ting-y/PyMySQL,jwjohns/PyMySQL,PyMySQL/Tornado-MySQL,pymysql/pymysql