python3: Use six.indexbytes for extracting single byte of data
python3: Use six.indexbytes for extracting single byte of data

Signed-off-by: IWAMOTO Toshihiro <8e41ae29694291a01b8efca6b4a0005a87ddb93e@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

fujita/ryu,iwaseyusuke/ryu,diogommartins/ryu,osrg/ryu,Tejas-Subramanya/RYU_MEC,sivaramakrishnansr/ryu,pichuang/ryu,StephenKing/ryu,shinpeimuraoka/ryu,fkakuma/ryu,zangree/ryu,habibiefaried/ryu,shinpeimuraoka/ryu,lagopus/ryu-lagopus-ext,takahashiminoru/ryu,elahejalalpour/ELRyu,zangree/ryu,zyq001/ryu,osrg/ryu,darjus-amzn/ryu,TakeshiTseng/ryu,habibiefaried/ryu,zyq001/ryu,lsqtongxin/ryu,hisaharu/ryu,takahashiminoru/ryu,iwaseyusuke/ryu,lsqtongxin/ryu,ttsubo/ryu,habibiefaried/ryu,sivaramakrishnansr/ryu,lagopus/ryu-lagopus-ext,OpenState-SDN/ryu,diogommartins/ryu,Zouyiran/ryu,iwaseyusuke/ryu,StephenKing/ryu,alanquillin/ryu,shinpeimuraoka/ryu,hisaharu/ryu,diogommartins/ryu,osrg/ryu,lagopus/ryu-lagopus-ext,darjus-amzn/ryu,takahashiminoru/ryu,ttsubo/ryu,lagopus/ryu-lagopus-ext,Tejas-Subramanya/RYU_MEC,hisaharu/ryu,TakeshiTseng/ryu,zangree/ryu,shinpeimuraoka/ryu,fujita/ryu,Tejas-Subramanya/RYU_MEC,fujita/ryu,sivaramakrishnansr/ryu,zangree/ryu,zyq001/ryu,StephenKing/ryu,hisaharu/ryu,lsqtongxin/ryu,elahejalalpour/ELRyu,OpenState-SDN/ryu,OpenState-SDN/ryu,pichuang/ryu,pichuang/ryu,alanquillin/ryu,lsqtongxin/ryu,elahejalalpour/ELRyu,gareging/SDN_Framework,gareging/SDN_Framework,gareging/SDN_Framework,ttsubo/ryu,StephenKing/ryu,ttsubo/ryu,zyq001/ryu,gareging/SDN_Framework,fkakuma/ryu,takahashiminoru/ryu,diogommartins/ryu,darjus-amzn/ryu,TakeshiTseng/ryu,TakeshiTseng/ryu,lsqtongxin/ryu,habibiefaried/ryu,John-Lin/ryu,sivaramakrishnansr/ryu,OpenState-SDN/ryu,fujita/ryu,Zouyiran/ryu,fkakuma/ryu,elahejalalpour/ELRyu,shinpeimuraoka/ryu,fkakuma/ryu,sivaramakrishnansr/ryu,zyq001/ryu,zangree/ryu,darjus-amzn/ryu,Tejas-Subramanya/RYU_MEC,osrg/ryu,Zouyiran/ryu,osrg/ryu,iwaseyusuke/ryu,alanquillin/ryu,John-Lin/ryu,elahejalalpour/ELRyu,habibiefaried/ryu,OpenState-SDN/ryu,alanquillin/ryu,pichuang/ryu,John-Lin/ryu,darjus-amzn/ryu,John-Lin/ryu,fujita/ryu,John-Lin/ryu,pichuang/ryu,gareging/SDN_Framework,ttsubo/ryu,Zouyiran/ryu,alanquillin/ryu,takahashiminoru/ryu,diogommartins/ryu,hisaharu/ryu,lagopus/ryu-lagopus-ext,fkakuma/ryu,Zouyiran/ryu,iwaseyusuke/ryu,StephenKing/ryu,Tejas-Subramanya/RYU_MEC,TakeshiTseng/ryu