of13: new OFPMatch field query api
of13: new OFPMatch field query api

an example:

    if 'ipv6_src' in match:
        print match['ipv6_src']

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

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