consensus: break out persist interface into separate struct
consensus: break out persist interface into separate struct

Signed-off-by: Simon Schubert <51a3d642c59e957126c8c9975e756dadd0226d4c@zurich.ibm.com>

bburgdave/fabric,tuand27613/obc-peer,hyperledger-archives/fabric,JonathanLevi/fabric,openblockchain/obc-peer,ariccy/fabric,gennadylaventman/fabric,adecaro/fabric,gennadylaventman/fabric,bren3582/fabric,gromeroar/fabric,murali-katipalli-dtcc/fabric,itp4IBM/fabric,andresgaragiola/fabric,adecaro/fabric,srderson/fabric,tuand27613/fabric,adecaro/fabric,jjjjibm/fabric,hyperledger-archives/fabric,bren3582/fabric,srderson/fabric,isghe/obc-peer,srderson/fabric,ariccy/fabric,gennadylaventman/fabric,openblockchain/obc-peer,andresgaragiola/fabric,gromeroar/fabric,jjjjibm/fabric,gromeroar/fabric,hyperledger-archives/fabric,JonathanLevi/fabric,tuand27613/obc-peer,bren3582/fabric,itp4IBM/fabric,ariccy/fabric,bburgdave/fabric,isghe/obc-peer,tuand27613/fabric,hyperledger-archives/fabric,bren3582/fabric,ahuachen/fabric,angrbrd/fabric,JonathanLevi/fabric,angrbrd/fabric,adecaro/fabric,binhn/obc-peer,srderson/fabric,angrbrd/fabric,angrbrd/fabric,gongsu832/fabric,andresgaragiola/fabric,adecaro/fabric,gromeroar/fabric,itp4IBM/fabric,itp4IBM/fabric,jjjjibm/fabric,gennadylaventman/fabric,itp4IBM/fabric,srderson/fabric,ariccy/fabric,murali-katipalli-dtcc/fabric,itp4IBM/fabric,angrbrd/fabric,ariccy/fabric,murali-katipalli-dtcc/fabric,tuand27613/obc-peer,murali-katipalli-dtcc/fabric,gennadylaventman/fabric,popldo/fabric,murali-katipalli-dtcc/fabric,ahuachen/fabric,hyperledger-archives/fabric,ahuachen/fabric,tuand27613/fabric,popldo/fabric,JonathanLevi/fabric,binhn/obc-peer,isghe/obc-peer,angrbrd/fabric,popldo/fabric,isghe/obc-peer,ahuachen/fabric,itp4IBM/fabric,binhn/obc-peer,gongsu832/fabric,ahuachen/fabric,tuand27613/fabric,bren3582/fabric,angrbrd/fabric,ahuachen/fabric,popldo/fabric,gromeroar/fabric,tuand27613/fabric,bburgdave/fabric,popldo/fabric,jjjjibm/fabric,tuand27613/fabric,ariccy/fabric,JonathanLevi/fabric,adecaro/fabric,jjjjibm/fabric,popldo/fabric,gennadylaventman/fabric,bren3582/fabric,bren3582/fabric,jjjjibm/fabric,gongsu832/fabric,gennadylaventman/fabric,andresgaragiola/fabric,bburgdave/fabric,bburgdave/fabric,gromeroar/fabric,andresgaragiola/fabric,JonathanLevi/fabric,andresgaragiola/fabric,isghe/obc-peer,srderson/fabric,ariccy/fabric,adecaro/fabric,openblockchain/obc-peer,tuand27613/fabric,hyperledger-archives/fabric,murali-katipalli-dtcc/fabric,ahuachen/fabric,gromeroar/fabric,jjjjibm/fabric,gongsu832/fabric,popldo/fabric,andresgaragiola/fabric,murali-katipalli-dtcc/fabric,srderson/fabric,JonathanLevi/fabric,hyperledger-archives/fabric