RyuApp.get_handlers: restructure code and add a comment
RyuApp.get_handlers: restructure code and add a comment

no functional changes.

Signed-off-by: YAMAMOTO Takashi <458bba2e4a8704776b33478100c98529b639cd9e@valinux.co.jp>
Signed-off-by: FUJITA Tomonori <93dac1fe9c4b2a3957982200319981492ad4976e@lab.ntt.co.jp>

darjus-amzn/ryu,fkakuma/ryu,zyq001/ryu,jalilm/ryu,StephenKing/summerschool-2015-ryu,jkoelker/ryu,castroflavio/ryu,StephenKing/ryu,Tejas-Subramanya/RYU_MEC,umkcdcrg01/ryu_openflow,John-Lin/ryu,ntts-clo/ryu,Tesi-Luca-Davide/ryu,gopchandani/ryu,iwaseyusuke/ryu,lzppp/mylearning,yamt/ryu,Zouyiran/ryu,jalilm/ryu,alanquillin/ryu,gareging/SDN_Framework,jalilm/ryu,OpenState-SDN/ryu,openvapour/ryu,torufuru/oolhackathon,shinpeimuraoka/ryu,torufuru/oolhackathon,alyosha1879/ryu,Zouyiran/ryu,fujita/ryu,diogommartins/ryu,jalilm/ryu,yamt/ryu,John-Lin/ryu,lagopus/ryu-lagopus-ext,zyq001/ryu,alyosha1879/ryu,elahejalalpour/ELRyu,gareging/SDN_Framework,darjus-amzn/ryu,Zouyiran/ryu,iwaseyusuke/ryu,John-Lin/ryu,evanscottgray/ryu,iwaseyusuke/ryu,jkoelker/ryu,StephenKing/ryu,gareging/SDN_Framework,Tejas-Subramanya/RYU_MEC,openvapour/ryu,alanquillin/ryu,shinpeimuraoka/ryu,Zouyiran/ryu,o3project/ryu-oe,lagopus/ryu-lagopus-ext,alanquillin/ryu,darjus-amzn/ryu,gopchandani/ryu,diogommartins/ryu,ntts-clo/mld-ryu,ttsubo/ryu,pichuang/ryu,zyq001/ryu,gopchandani/ryu,fkakuma/ryu,OpenState-SDN/ryu,takahashiminoru/ryu,ynkjm/ryu,jazzmes/ryu,StephenKing/summerschool-2015-ryu,habibiefaried/ryu,osrg/ryu,umkcdcrg01/ryu_openflow,lzppp/mylearning,zangree/ryu,OpenState-SDN/ryu,openvapour/ryu,hisaharu/ryu,yamt/ryu,lsqtongxin/ryu,lsqtongxin/ryu,ysywh/ryu,lagopus/ryu-lagopus-ext,elahejalalpour/ELRyu,StephenKing/summerschool-2015-ryu,Tejas-Subramanya/RYU_MEC,Tejas-Subramanya/RYU_MEC,ysywh/ryu,TakeshiTseng/ryu,ttsubo/ryu,umkcdcrg01/ryu_openflow,takahashiminoru/ryu,o3project/ryu-oe,ntts-clo/mld-ryu,hisaharu/ryu,habibiefaried/ryu,lsqtongxin/ryu,TakeshiTseng/ryu,jkoelker/ryu,alyosha1879/ryu,fkakuma/ryu,zyq001/ryu,hisaharu/ryu,evanscottgray/ryu,pichuang/ryu,sivaramakrishnansr/ryu,haniehrajabi/ryu,shinpeimuraoka/ryu,iwaseyusuke/ryu,sivaramakrishnansr/ryu,Tesi-Luca-Davide/ryu,elahejalalpour/ELRyu,muzixing/ryu,sivaramakrishnansr/ryu,StephenKing/ryu,sivaramakrishnansr/ryu,Tesi-Luca-Davide/ryu,elahejalalpour/ELRyu,evanscottgray/ryu,shinpeimuraoka/ryu,shinpeimuraoka/ryu,ntts-clo/ryu,habibiefaried/ryu,ttsubo/ryu,lagopus/ryu-lagopus-ext,Tesi-Luca-Davide/ryu,OpenState-SDN/ryu,fujita/ryu,muzixing/ryu,John-Lin/ryu,ttsubo/ryu,fkakuma/ryu,habibiefaried/ryu,osrg/ryu,castroflavio/ryu,zangree/ryu,gopchandani/ryu,darjus-amzn/ryu,zangree/ryu,openvapour/ryu,ynkjm/ryu,habibiefaried/ryu,jazzmes/ryu,alanquillin/ryu,gopchandani/ryu,haniehrajabi/ryu,ynkjm/ryu,diogommartins/ryu,iwaseyusuke/ryu,jazzmes/ryu,sivaramakrishnansr/ryu,takahashiminoru/ryu,lagopus/ryu-lagopus-ext,lsqtongxin/ryu,yamada-h/ryu,zyq001/ryu,jalilm/ryu,fujita/ryu,StephenKing/summerschool-2015-ryu,osrg/ryu,muzixing/ryu,darjus-amzn/ryu,pichuang/ryu,StephenKing/summerschool-2015-ryu,haniehrajabi/ryu,yamt/ryu,John-Lin/ryu,pichuang/ryu,haniehrajabi/ryu,zangree/ryu,ynkjm/ryu,openvapour/ryu,umkcdcrg01/ryu_openflow,diogommartins/ryu,hisaharu/ryu,Tejas-Subramanya/RYU_MEC,yamada-h/ryu,takahashiminoru/ryu,fujita/ryu,StephenKing/ryu,ysywh/ryu,diogommartins/ryu,OpenState-SDN/ryu,TakeshiTseng/ryu,haniehrajabi/ryu,gareging/SDN_Framework,pichuang/ryu,TakeshiTseng/ryu,Zouyiran/ryu,lzppp/mylearning,Tesi-Luca-Davide/ryu,ynkjm/ryu,ysywh/ryu,osrg/ryu,fkakuma/ryu,ttsubo/ryu,yamt/ryu,umkcdcrg01/ryu_openflow,zangree/ryu,alanquillin/ryu,fujita/ryu,muzixing/ryu,osrg/ryu,StephenKing/ryu,alyosha1879/ryu,ysywh/ryu,lzppp/mylearning,torufuru/oolhackathon,castroflavio/ryu,elahejalalpour/ELRyu,gareging/SDN_Framework,lzppp/mylearning,hisaharu/ryu,TakeshiTseng/ryu,takahashiminoru/ryu,muzixing/ryu,lsqtongxin/ryu