Add a JoinStrategy enum
Add a JoinStrategy enum

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eCocoa,walkingsmarts/ReactiveCocoa,brasbug/ReactiveCocoa,emodeqidao/ReactiveCocoa,yytong/ReactiveCocoa,GuitarPlayer-Ma/ReactiveCocoa,wangqi211/ReactiveCocoa,victorlin/ReactiveCocoa,alvinvarghese/ReactiveCocoa,longv2go/ReactiveCocoa,LHDsimon/ReactiveCocoa,DreamHill/ReactiveCocoa,FelixYin66/ReactiveCocoa,kaylio/ReactiveCocoa,leichunfeng/ReactiveCocoa,kiurentu/ReactiveCocoa,AlanJN/ReactiveCocoa,on99/ReactiveCocoa,natan/ReactiveCocoa,smilypeda/ReactiveCocoa,mattpetters/ReactiveCocoa,tornade0913/ReactiveCocoa,xumaolin/ReactiveCocoa,ddc391565320/ReactiveCocoa,zhenlove/ReactiveCocoa,ikesyo/ReactiveCocoa,Farteen/ReactiveCocoa,WEIBP/ReactiveCocoa,ohwutup/ReactiveCocoa,mtxs007/ReactiveCocoa,terry408911/ReactiveCocoa,sandyway/ReactiveCocoa,ioshger0125/ReactiveCocoa,monkeydbobo/ReactiveCocoa,dachaoisme/ReactiveCocoa,smilypeda/ReactiveCocoa,CCOOOOLL/ReactiveCocoa,takeshineshiro/ReactiveCocoa,ericzhou2008/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,jeelun/ReactiveCocoa,imkerberos/ReactiveCocoa,Pingco/ReactiveCocoa,DongDongDongDong/ReactiveCocoa,buildo/ReactiveCocoa,yangshengchaoios/ReactiveCocoa,Ethan89/ReactiveCocoa,shuxiashusheng/ReactiveCocoa,Rupert-RR/ReactiveCocoa,chao95957/ReactiveCocoa,leelili/ReactiveCocoa,xiaobing2007/ReactiveCocoa,sdhzwm/ReactiveCocoa,sugar2010/ReactiveCocoa,AndyZhaoHe/ReactiveCocoa,natan/ReactiveCocoa,yonekawa/ReactiveCocoa,zxq3220122/ReactiveCocoa,Juraldinio/ReactiveCocoa,KJin99/ReactiveCocoa,kevin-zqw/ReactiveCocoa,isghe/ReactiveCocoa,richeterre/ReactiveCocoa,nickcheng/ReactiveCocoa,qq644531343/ReactiveCocoa,msdgwzhy6/ReactiveCocoa,paulyoung/ReactiveCocoa,DongDongDongDong/ReactiveCocoa,ddc391565320/ReactiveCocoa,hilllinux/ReactiveCocoa,pzw224/ReactiveCocoa,sujeking/ReactiveCocoa,SuPair/ReactiveCocoa,calebd/ReactiveCocoa,tonyarnold/ReactiveCocoa,taylormoonxu/ReactiveCocoa,fanghao085/ReactiveCocoa,dullgrass/ReactiveCocoa,goodheart/ReactiveCocoa,BrooksWon/ReactiveCocoa,zhaoguohui/ReactiveCocoa,loupman/ReactiveCocoa,dachaoisme/ReactiveCocoa,llb1119/test,luerhouhou/ReactiveCocoa,CQXfly/ReactiveCocoa,kaylio/ReactiveCocoa,zhukaixy/ReactiveCocoa,llb1119/test,cnbin/ReactiveCocoa,xulibao/ReactiveCocoa,isghe/ReactiveCocoa,nikita-leonov/ReactiveCocoa,msdgwzhy6/ReactiveCocoa,zhukaixy/ReactiveCocoa,valleyman86/ReactiveCocoa,liufeigit/ReactiveCocoa,yizzuide/ReactiveCocoa,pzw224/ReactiveCocoa,nikita-leonov/ReactiveCocoa,zzzworm/ReactiveCocoa,Farteen/ReactiveCocoa,towik/ReactiveCocoa,ztchena/ReactiveCocoa,Ethan89/ReactiveCocoa,kevin-zqw/ReactiveCocoa,hoanganh6491/ReactiveCocoa,BrooksWon/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,vincentiss/ReactiveCocoa,zhiwen1024/ReactiveCocoa,almassapargali/ReactiveCocoa,loupman/ReactiveCocoa,OneSmallTree/ReactiveCocoa,OnTheWay1988/ReactiveCocoa,JohnJin007/ReactiveCocoa,WEIBP/ReactiveCocoa,Ricowere/ReactiveCocoa,mtxs007/ReactiveCocoa,add715/ReactiveCocoa,yaoxiaoyong/ReactiveCocoa,zhigang1992/ReactiveCocoa,ohwutup/ReactiveCocoa,zxq3220122/ReactiveCocoa,brasbug/ReactiveCocoa,yonekawa/ReactiveCocoa,dz1111/ReactiveCocoa,jsslai/ReactiveCocoa,ceekayel/ReactiveCocoa,yoichitgy/ReactiveCocoa,gengjf/ReactiveCocoa,huiping192/ReactiveCocoa,takeshineshiro/ReactiveCocoa,emodeqidao/ReactiveCocoa,howandhao/ReactiveCocoa,BlessNeo/ReactiveCocoa,cstars135/ReactiveCocoa,Khan/ReactiveCocoa,Juraldinio/ReactiveCocoa,wpstarnice/ReactiveCocoa,yangshengchaoios/ReactiveCocoa,almassapargali/ReactiveCocoa,brasbug/ReactiveCocoa,natestedman/ReactiveCocoa,zhiwen1024/ReactiveCocoa,richeterre/ReactiveCocoa,mtxs007/ReactiveCocoa,jrmiddle/ReactiveCocoa,ericzhou2008/ReactiveCocoa,longv2go/ReactiveCocoa,jsslai/ReactiveCocoa,KJin99/ReactiveCocoa,libiao88/ReactiveCocoa,vincentiss/ReactiveCocoa,Ricowere/ReactiveCocoa,on99/ReactiveCocoa,tzongw/ReactiveCocoa,xumaolin/ReactiveCocoa,cogddo/ReactiveCocoa,shuxiashusheng/ReactiveCocoa,jackywpy/ReactiveCocoa,libiao88/ReactiveCocoa,jsslai/ReactiveCocoa,qq644531343/ReactiveCocoa,OnTheWay1988/ReactiveCocoa,zxq3220122/ReactiveCocoa,Rupert-RR/ReactiveCocoa,xulibao/ReactiveCocoa,CQXfly/ReactiveCocoa,ReactiveCocoa/ReactiveSwift,GuitarPlayer-Ma/ReactiveCocoa,ceekayel/ReactiveCocoa,dskatz22/ReactiveCocoa,ztchena/ReactiveCocoa,GuitarPlayer-Ma/ReactiveCocoa,ceekayel/ReactiveCocoa,bensonday/ReactiveCocoa,DongDongDongDong/ReactiveCocoa,chieryw/ReactiveCocoa,nickcheng/ReactiveCocoa,jeelun/ReactiveCocoa,esttorhe/ReactiveCocoa,FelixYin66/ReactiveCocoa,LHDsimon/ReactiveCocoa,luerhouhou/ReactiveCocoa,xulibao/ReactiveCocoa,imkerberos/ReactiveCocoa,PSPDFKit-labs/ReactiveCocoa,tonyli508/ReactiveCocoa,j364960953/ReactiveCocoa,tiger8888/ReactiveCocoa,xiaoliyang/ReactiveCocoa,gengjf/ReactiveCocoa,FelixYin66/ReactiveCocoa,terry408911/ReactiveCocoa,hilllinux/ReactiveCocoa,natestedman/ReactiveCocoa,Eveian/ReactiveCocoa,KuPai32G/ReactiveCocoa,towik/ReactiveCocoa,Ray0218/ReactiveCocoa,richeterre/ReactiveCocoa,fhchina/ReactiveCocoa,mxxiv/ReactiveCocoa,Pingco/ReactiveCocoa,kevin-zqw/ReactiveCocoa,AndyZhaoHe/ReactiveCocoa,hbucius/ReactiveCocoa,Eveian/ReactiveCocoa,Farteen/ReactiveCocoa,hoanganh6491/ReactiveCocoa,ddc391565320/ReactiveCocoa,stevielu/ReactiveCocoa,yonekawa/ReactiveCocoa,andersio/ReactiveCocoa,AndyZhaoHe/ReactiveCocoa,eyu1988/ReactiveCocoa,hj3938/ReactiveCocoa,dachaoisme/ReactiveCocoa,fhchina/ReactiveCocoa,on99/ReactiveCocoa,calebd/ReactiveCocoa,cogddo/ReactiveCocoa,DreamHill/ReactiveCocoa,juliangrosshauser/ReactiveCocoa,DreamHill/ReactiveCocoa,icepy/ReactiveCocoa,jaylib/ReactiveCocoa,sdhzwm/ReactiveCocoa,takeshineshiro/ReactiveCocoa,hilllinux/ReactiveCocoa,yoichitgy/ReactiveCocoa,almassapargali/ReactiveCocoa,200895045/ReactiveCocoa,bensonday/ReactiveCocoa,Ricowere/ReactiveCocoa,walkingsmarts/ReactiveCocoa,Juraldinio/ReactiveCocoa,WEIBP/ReactiveCocoa,yizzuide/ReactiveCocoa,stevielu/ReactiveCocoa,RuiAAPeres/ReactiveCocoa,lixar/ReactiveCocoa,andersio/ReactiveCocoa,mxxiv/ReactiveCocoa,gengjf/ReactiveCocoa,huiping192/ReactiveCocoa,monkeydbobo/ReactiveCocoa,sdhzwm/ReactiveCocoa,jaylib/ReactiveCocoa,tiger8888/ReactiveCocoa,jam891/ReactiveCocoa,OneSmallTree/ReactiveCocoa,alvinvarghese/ReactiveCocoa,hoanganh6491/ReactiveCocoa,BlessNeo/ReactiveCocoa,zhenlove/ReactiveCocoa,zhaoguohui/ReactiveCocoa,liufeigit/ReactiveCocoa,juliangrosshauser/ReactiveCocoa,zzqiltw/ReactiveCocoa,emodeqidao/ReactiveCocoa,j364960953/ReactiveCocoa,mattpetters/ReactiveCocoa,ShawnLeee/ReactiveCocoa