Teach ProcessNewBlock() how to handle a reindex
Teach ProcessNewBlock() how to handle a reindex

During a reindex, we don't have nodes to send messages to, nor do
we have a previous block hash for the genesis block, so we must
take those conditions into account.

Mrs-X/Darknet,slingcoin/sling-market,Bloom-Project/Bloom,Mrs-X/Darknet,presstab/PIVX,keesdewit82/LasVegasCoin,Mrs-X/PIVX,Mrs-X/PIVX,slingcoin/sling-market,48thct2jtnf/P,48thct2jtnf/P,PIVX-Project/PIVX,benzmuircroft/REWIRE.io,PIVX-Project/PIVX,DMDcoin/Diamond,Bloom-Project/Bloom,presstab/PIVX,PIVX-Project/PIVX,Vsync-project/Vsync,keesdewit82/LasVegasCoin,ColossusCoinXT/ColossusCoinXT,Vsync-project/Vsync,LIMXTEC/DMDv3,benzmuircroft/REWIRE.io,dev1972/Satellitecoin,ColossusCoinXT/ColossusCoinXT,Mrs-X/Darknet,48thct2jtnf/P,CoinProjects/AmsterdamCoin-v4,LIMXTEC/DMDv3,PIVX-Project/PIVX,Mrs-X/PIVX,npccoin/npccoin,Darknet-Crypto/Darknet,dev1972/Satellitecoin,ColossusCoinXT/ColossusCoinXT,CoinProjects/AmsterdamCoin-v4,slingcoin/sling-market,keesdewit82/LasVegasCoin,PIVX-Project/PIVX,DMDcoin/Diamond,PIVX-Project/PIVX,DMDcoin/Diamond,midnight-miner/LasVegasCoin,keesdewit82/LasVegasCoin,ColossusCoinXT/ColossusCoinXT,ColossusCoinXT/ColossusCoinXT,pelorusjack/BlockDX,pelorusjack/BlockDX,npccoin/npccoin,ColossusCoinXT/ColossusCoinXT,Bloom-Project/Bloom,Bloom-Project/Bloom,pelorusjack/BlockDX,Vsync-project/Vsync,PIVX-Project/PIVX,benzmuircroft/REWIRE.io,48thct2jtnf/P,Bloom-Project/Bloom,Darknet-Crypto/Darknet,slingcoin/sling-market,Mrs-X/Darknet,Vsync-project/Vsync,Darknet-Crypto/Darknet,npccoin/npccoin,presstab/PIVX,LIMXTEC/DMDv3,LIMXTEC/DMDv3,dev1972/Satellitecoin,pelorusjack/BlockDX,Darknet-Crypto/Darknet,CoinProjects/AmsterdamCoin-v4,LIMXTEC/DMDv3,keesdewit82/LasVegasCoin,Mrs-X/PIVX,Darknet-Crypto/Darknet,presstab/PIVX,Vsync-project/Vsync,pelorusjack/BlockDX,DMDcoin/Diamond,npccoin/npccoin,Mrs-X/PIVX,PIVX-Project/PIVX,Mrs-X/PIVX,Bloom-Project/Bloom,dev1972/Satellitecoin,benzmuircroft/REWIRE.io,pelorusjack/BlockDX,CoinProjects/AmsterdamCoin-v4,npccoin/npccoin,DMDcoin/Diamond,presstab/PIVX,benzmuircroft/REWIRE.io,LIMXTEC/DMDv3,DMDcoin/Diamond,dev1972/Satellitecoin,Mrs-X/Darknet,dev1972/Satellitecoin,CoinProjects/AmsterdamCoin-v4,48thct2jtnf/P,benzmuircroft/REWIRE.io,Darknet-Crypto/Darknet,midnight-miner/LasVegasCoin,slingcoin/sling-market,midnight-miner/LasVegasCoin,CoinProjects/AmsterdamCoin-v4,Vsync-project/Vsync,midnight-miner/LasVegasCoin,npccoin/npccoin,48thct2jtnf/P,slingcoin/sling-market,keesdewit82/LasVegasCoin,midnight-miner/LasVegasCoin,PIVX-Project/PIVX,Mrs-X/Darknet,midnight-miner/LasVegasCoin,presstab/PIVX