removed unnecessary iostream header form serializer.h
removed unnecessary iostream header form serializer.h

SRCH2/srch2-ngn,SRCH2/srch2-ngn,SRCH2/srch2-ngn,SRCH2/srch2-ngn,SRCH2/srch2-ngn,SRCH2/srch2-ngn,SRCH2/srch2-ngn