Bug fix: avoid rescanning block files.
Bug fix: avoid rescanning block files.

machinecoin-project/machinecoin-blockchainexplorer-abe,gjhiggins/abe-bee2,Serya05/bitcoin-abe,machado-rev/HTMLCoinExplorer,ultracoindev/ultracoin-abe,Cybnate/NuBits-Abe-explorer,BuckyGreen/latiumexplorer,Rimbit/RimbitExplorer,CraigsCoin/abe-craigscoin,gjhiggins/abe-bee2,Cybnate/NuBits-Abe-explorer,jeorgen/bitcoin-abe,muchbeli/bitcoin-abe,mmitech/bitcoin-abe,Dilmacoin/dilmacoin-abe,n00bsys0p/altcoin-abe,Rimbit/RimbitExplorer,muchbeli/bitcoin-abe,gjhiggins/altcoin-abe,Max-Coin/maxcoin-abe,Rimbit/RimbitExplorer,machinecoin-project/machinecoin-blockchainexplorer-abe,jonnynewbs/bitcoin-abe,gjhiggins/abe-bee2,jeromewu/bitcoin-abe-opennet,machado-rev/HTMLCoinExplorer,Cybnate/NuBits-Abe-explorer,Dilmacoin/dilmacoin-abe,Max-Coin/maxcoin-abe,cryptapus/bitcoin-abe,ultracoindev/ultracoin-abe,muchbeli/bitcoin-abe,Rimbit/RimbitExplorer,CraigsCoin/abe-craigscoin,jonnynewbs/bitcoin-abe,gjhiggins/chaincoin-abe,UdjinM6/darkcoin-abe,sacarlson/bitcoin-abe,ultracoindev/ultracoin-abe,ultracoindev/ultracoin-abe,Cybnate/NuBits-Abe-explorer,BuckyGreen/latiumexplorer,Serya05/bitcoin-abe,mmitech/bitcoin-abe,BuckyGreen/latiumexplorer,cryptapus/bitcoin-abe,MatthewLM/PeercoinAbeExplorer,MatthewLM/PeercoinAbeExplorer,UdjinM6/darkcoin-abe,ultracoindev/ultracoin-abe,jeorgen/bitcoin-abe,MatthewLM/PeercoinAbeExplorer,muchbeli/bitcoin-abe,n00bsys0p/altcoin-abe,Cybnate/NuBits-Abe-explorer,machado-rev/HTMLCoinExplorer,leadcoin-reboot/leadcoin-abe,BuckyGreen/latiumexplorer,jeromewu/bitcoin-abe-opennet,MatthewLM/PeercoinAbeExplorer,machado-rev/HTMLCoinExplorer,leadcoin-reboot/leadcoin-abe,gjhiggins/altcoin-abe,gjhiggins/chaincoin-abe