Specialize hash<basic_fbstring> in correct namespaces
Specialize hash<basic_fbstring> in correct namespaces

Summary:
- Use the BOOST_STD_EXTENSION_NAMESPACE macro to pick the namespace to
use for hash specializations

Test Plan:
- fbconfig -r unicorn/utils/ && fbmake opt
- fbconfig -r folly && fbmake runtests
- Build in fbobjc with libc++
@override-unit-failures

Reviewed By: rajatr@fb.com

FB internal diff: D1153422

Blame Revision: D1152140


gavioto/folly,charsyam/folly,zhiweicai/folly,ykarlsbrun/folly,renyinew/folly,bikong2/folly,guker/folly,bikong2/folly,ykarlsbrun/folly,constantine001/folly,clearlinux/folly,clearlylin/folly,floxard/folly,kernelim/folly,renyinew/folly,loverszhaokai/folly,reddit/folly,PPC64/folly,SeanRBurton/folly,rklabs/folly,PPC64/folly,theiver9827/folly,shaobz/folly,tomhughes/folly,renyinew/folly,tempbottle/folly,tempbottle/folly,reddit/folly,stonegithubs/folly,KSreeHarsha/folly,doctaweeks/folly,facebook/folly,loversInJapan/folly,sakishum/folly,Eagle-X/folly,Eagle-X/folly,bowlofstew/folly,doctaweeks/folly,bikong2/folly,cppfool/folly,chjp2046/folly,PPC64/folly,clearlinux/folly,tempbottle/folly,fw1121/folly,arg0/folly,Hincoin/folly,Orvid/folly,gaoyingie/folly,theiver9827/folly,rklabs/folly,KSreeHarsha/folly,sonnyhu/folly,leolujuyi/folly,upsoft/folly,chjp2046/folly,raphaelamorim/folly,wildinto/folly,mqeizi/folly,colemancda/folly,gaoyingie/folly,floxard/folly,facebook/folly,wildinto/folly,gaoyingie/folly,arg0/folly,lifei/folly,charsyam/folly,xzmagic/folly,bowlofstew/folly,tomhughes/folly,theiver9827/folly,cole14/folly,romange/folly,nickhen/folly,cppfool/folly,bobegir/folly,brunomorishita/folly,alexst07/folly,bowlofstew/folly,reddit/folly,arg0/folly,guker/folly,rklabs/folly,nickhen/folly,mqeizi/folly,yangjin-unique/folly,hongliangzhao/folly,cppfool/folly,shaobz/folly,hongliangzhao/folly,CJstar/folly,yangjin-unique/folly,alexst07/folly,Eagle-X/folly,hongliangzhao/folly,constantine001/folly,project-zerus/folly,raphaelamorim/folly,tomhughes/folly,fw1121/folly,CJstar/folly,PoisonBOx/folly,romange/folly,hongliangzhao/folly,rklabs/folly,wildinto/folly,clearlylin/folly,Hincoin/folly,yangjin-unique/folly,sonnyhu/folly,gavioto/folly,SeanRBurton/folly,SammyK/folly,upsoft/folly,reddit/folly,doctaweeks/folly,shaobz/folly,wildinto/folly,charsyam/folly,mqeizi/folly,leolujuyi/folly,doctaweeks/folly,sakishum/folly,raphaelamorim/folly,cole14/folly,SammyK/folly,PoisonBOx/folly,leolujuyi/folly,floxard/folly,shaobz/folly,upsoft/folly,gavioto/folly,CJstar/folly,constantine001/folly,brunomorishita/folly,SeanRBurton/folly,Eagle-X/folly,clearlinux/folly,Eagle-X/folly,cole14/folly,chjp2046/folly,facebook/folly,renyinew/folly,brunomorishita/folly,xzmagic/folly,yangjin-unique/folly,xzmagic/folly,raphaelamorim/folly,loverszhaokai/folly,juniway/folly,ykarlsbrun/folly,wildinto/folly,loversInJapan/folly,fw1121/folly,Hincoin/folly,fw1121/folly,zhiweicai/folly,constantine001/folly,guker/folly,loversInJapan/folly,ykarlsbrun/folly,clearlylin/folly,lifei/folly,floxard/folly,bobegir/folly,Orvid/folly,leolujuyi/folly,hongliangzhao/folly,gaoyingie/folly,PPC64/folly,lifei/folly,SeanRBurton/folly,Hincoin/folly,yangjin-unique/folly,zhiweicai/folly,stonegithubs/folly,KSreeHarsha/folly,CJstar/folly,romange/folly,tempbottle/folly,colemancda/folly,xzmagic/folly,bsampath/folly,lifei/folly,bowlofstew/folly,lifei/folly,gavioto/folly,sakishum/folly,bobegir/folly,tomhughes/folly,project-zerus/folly,sonnyhu/folly,bobegir/folly,colemancda/folly,CJstar/folly,floxard/folly,nickhen/folly,kernelim/folly,sakishum/folly,romange/folly,tomhughes/folly,SammyK/folly,bsampath/folly,kernelim/folly,clearlylin/folly,fw1121/folly,alexst07/folly,project-zerus/folly,xzmagic/folly,PoisonBOx/folly,KSreeHarsha/folly,project-zerus/folly,loverszhaokai/folly,loverszhaokai/folly,sakishum/folly,facebook/folly,mqeizi/folly,stonegithubs/folly,upsoft/folly,colemancda/folly,romange/folly,juniway/folly,loverszhaokai/folly,mqeizi/folly,loversInJapan/folly,KSreeHarsha/folly,zhiweicai/folly,renyinew/folly,clearlinux/folly,brunomorishita/folly,guker/folly,stonegithubs/folly,kernelim/folly,bobegir/folly,bikong2/folly,doctaweeks/folly,bsampath/folly,theiver9827/folly,PPC64/folly,juniway/folly,upsoft/folly,cole14/folly,chjp2046/folly,juniway/folly,ykarlsbrun/folly,cppfool/folly,juniway/folly,rklabs/folly,PoisonBOx/folly,sonnyhu/folly,shaobz/folly,nickhen/folly,reddit/folly,clearlinux/folly,Hincoin/folly,chjp2046/folly,bowlofstew/folly,SammyK/folly,project-zerus/folly,PoisonBOx/folly,facebook/folly,colemancda/folly,loversInJapan/folly,constantine001/folly,theiver9827/folly,cole14/folly,brunomorishita/folly,stonegithubs/folly,bsampath/folly,guker/folly,alexst07/folly,Orvid/folly,bsampath/folly,tempbottle/folly,gaoyingie/folly,zhiweicai/folly,raphaelamorim/folly,clearlylin/folly,SammyK/folly,cppfool/folly,leolujuyi/folly,alexst07/folly,Orvid/folly,kernelim/folly,charsyam/folly,Orvid/folly,arg0/folly,sonnyhu/folly,SeanRBurton/folly,gavioto/folly,bikong2/folly,nickhen/folly,arg0/folly