Fix minor backward incompatibility
Fix minor backward incompatibility

The key refactor changed the way unencrypted private keys with compressed
public key are stored in the wallet. Apparently older versions relied on
this to verify the correctness of stored keys.

Note that earlier pre-release versions do risk creating wallets that can
not be opened by 0.8.3 and earlier.

marscoin/marscoin,WorldcoinGlobal/WorldcoinLegacy,vertcoin/eyeglass,Czarcoin/czarcoin,shadowoneau/ozcoin,brightcoin/brightcoin,Dajackal/Ronpaulcoin,Rav3nPL/doubloons-08,nanocoins/mycoin,kryptokredyt/ProjektZespolowyCoin,coinkeeper/anoncoin_20150330_fixes,nanocoins/mycoin,coinkeeper/2015-06-22_18-46_razor,Electronic-Gulden-Foundation/egulden,earthcoinproject/earthcoin,koharjidan/litecoin,bootycoin-project/bootycoin,privatecoin/privatecoin,coinkeeper/2015-06-22_19-13_florincoin,WorldcoinGlobal/WorldcoinLegacy,zzkt/solarcoin,Czarcoin/czarcoin,scamcoinz/scamcoin,Ziftr/litecoin,greencoin-dev/greencoin-dev,richo/dongcoin,privatecoin/privatecoin,Bluejudy/worldcoin,neutrinofoundation/neutrino-digital-currency,mooncoin-project/mooncoin-landann,oklink-dev/litecoin_block,greencoin-dev/greencoin-dev,brishtiteveja/sherlockholmescoin,cqtenq/Feathercoin,franko-org/franko,chrisfranko/aiden,shurcoin/shurcoin,neutrinofoundation/neutrino-digital-currency,stamhe/litecoin,Czarcoin/czarcoin,collapsedev/circlecash,IlfirinCano/shavercoin,koharjidan/litecoin,ronpaulcoin/ronpaulcoin,ronpaulcoin/ronpaulcoin,united-scrypt-coin-project/unitedscryptcoin,icook/vertcoin,Anoncoin/anoncoin,zebrains/Blotter,earthcoinproject/earthcoin,coinkeeper/2015-06-22_18-46_razor,coinkeeper/2015-06-22_19-13_florincoin,brightcoin/brightcoin,marscoin/marscoin,micryon/GPUcoin,coinkeeper/anoncoin_20150330_fixes,marscoin/marscoin,plankton12345/litecoin,bitgoldcoin-project/bitgoldcoin,stamhe/litecoin,richo/dongcoin,privatecoin/privatecoin,oklink-dev/litecoin_block,CrimeaCoin/crimeacoin,shapiroisme/datadollar,ANCompany/birdcoin-dev,coinkeeper/2015-04-19_21-20_litecoindark,enlighter/Feathercoin,Bluejudy/worldcoin,Ziftr/litecoin,ANCompany/birdcoin-dev,coinkeeper/2015-06-22_18-30_anoncoin,oklink-dev/litecoin_block,neutrinofoundation/neutrino-digital-currency,Coinfigli/coinfigli,cinnamoncoin/Feathercoin,shadowoneau/ozcoin,shadowoneau/ozcoin,gwangjin2/gwangcoin-core,coinkeeper/2015-06-22_18-51_vertcoin,vertcoin/eyeglass,wekuiz/wekoin,razor-coin/razor,WorldcoinGlobal/WorldcoinLegacy,micryon/GPUcoin,ronpaulcoin/ronpaulcoin,Ziftr/litecoin,cryptcoins/cryptcoin,mooncoin-project/mooncoin-landann,Coinfigli/coinfigli,brishtiteveja/sherlockholmescoin,alexandrcoin/vertcoin,Rav3nPL/doubloons-08,Litecoindark/LTCD,Cancercoin/Cancercoin,coinkeeper/2015-04-19_21-20_litecoindark,zzkt/solarcoin,KaSt/equikoin,cinnamoncoin/Feathercoin,Dajackal/Ronpaulcoin,cinnamoncoin/Feathercoin,Anoncoin/anoncoin,CrimeaCoin/crimeacoin,coinkeeper/2015-06-22_18-30_anoncoin,razor-coin/razor,KaSt/equikoin,bitgoldcoin-project/bitgoldcoin,ohac/sakuracoin,cinnamoncoin/Feathercoin,WorldcoinGlobal/WorldcoinLegacy,koharjidan/litecoin,zemrys/vertcoin,tensaix2j/bananacoin,ohac/sha1coin,brightcoin/brightcoin,Tetcoin/tetcoin,plankton12345/litecoin,saydulk/Feathercoin,brishtiteveja/sherlockholmescoin,privatecoin/privatecoin,vertcoin/eyeglass,shurcoin/shurcoin,netswift/vertcoin,Cancercoin/Cancercoin,coinkeeper/2015-06-22_18-46_razor,united-scrypt-coin-project/unitedscryptcoin,Anoncoin/anoncoin,Bluejudy/worldcoin,ohac/sakuracoin,bootycoin-project/bootycoin,micryon/GPUcoin,worldcoinproject/worldcoin-v0.8,enlighter/Feathercoin,IlfirinIlfirin/shavercoin,Checkcoin/checkcoin,ohac/sakuracoin,ohac/sakuracoin,coinkeeper/2015-06-22_19-19_worldcoin,worldcoinproject/worldcoin-v0.8,DrCrypto/darkcoin,worldcoinproject/worldcoin-v0.8,Electronic-Gulden-Foundation/egulden,nanocoins/mycoin,DrCrypto/darkcoin,mrtexaznl/mediterraneancoin,shurcoin/shurcoin,worldcoinproject/worldcoin-v0.8,greencoin-dev/greencoin-dev,tensaix2j/bananacoin,greencoin-dev/greencoin-dev,dakk/soundcoin,IlfirinCano/shavercoin,qreatora/worldcoin-v0.8,novaexchange/EAC,ronpaulcoin/ronpaulcoin,richo/dongcoin,DrCrypto/darkcoin,kryptokredyt/ProjektZespolowyCoin,bitgoldcoin-project/bitgoldcoin,earthcoinproject/earthcoin,icook/vertcoin,razor-coin/razor,coinkeeper/2015-06-22_18-30_anoncoin,mrtexaznl/mediterraneancoin,Czarcoin/czarcoin,netswift/vertcoin,jiffe/cosinecoin,chrisfranko/aiden,franko-org/franko,zzkt/solarcoin,coinkeeper/2015-06-22_18-51_vertcoin,tensaix2j/bananacoin,icook/vertcoin,marscoin/marscoin,chrisfranko/aiden,franko-org/franko,zzkt/solarcoin,Coinfigli/coinfigli,novaexchange/EAC,enlighter/Feathercoin,Coinfigli/coinfigli,degenorate/Deftcoin,mooncoin-project/mooncoin-landann,Coinfigli/coinfigli,wekuiz/wekoin,micryon/GPUcoin,ccoin-project/ccoin,coinkeeper/2015-06-22_18-30_anoncoin,kryptokredyt/ProjektZespolowyCoin,degenorate/Deftcoin,oklink-dev/litecoin_block,okinc/litecoin,gwangjin2/gwangcoin-core,shapiroisme/datadollar,dakk/soundcoin,Dajackal/Ronpaulcoin,ohac/sakuracoin,vertcoin/eyeglass,scamcoinz/scamcoin,cryptcoins/cryptcoin,coinkeeper/2015-06-22_19-13_florincoin,greencoin-dev/greencoin-dev,dakk/soundcoin,CrimeaCoin/crimeacoin,Rav3nPL/doubloons-08,Tetcoin/tetcoin,coinkeeper/2015-06-22_18-51_vertcoin,coinkeeper/2015-04-19_21-20_litecoindark,Cancercoin/Cancercoin,zebrains/Blotter,ccoin-project/ccoin,scamcoinz/scamcoin,united-scrypt-coin-project/unitedscryptcoin,saydulk/Feathercoin,mrtexaznl/mediterraneancoin,stamhe/litecoin,koharjidan/litecoin,coinkeeper/2015-06-22_18-51_vertcoin,coinkeeper/anoncoin_20150330_fixes,shadowoneau/ozcoin,okinc/litecoin,CrimeaCoin/crimeacoin,coinkeeper/2015-06-22_19-19_worldcoin,mooncoin-project/mooncoin-landann,Litecoindark/LTCD,icook/vertcoin,chrisfranko/aiden,IlfirinIlfirin/shavercoin,Litecoindark/LTCD,gwangjin2/gwangcoin-core,novaexchange/EAC,chrisfranko/aiden,qreatora/worldcoin-v0.8,Litecoindark/LTCD,scamcoinz/scamcoin,coinkeeper/2015-04-19_21-20_litecoindark,ANCompany/birdcoin-dev,united-scrypt-coin-project/unitedscryptcoin,tensaix2j/bananacoin,dakk/soundcoin,cinnamoncoin/Feathercoin,Dajackal/Ronpaulcoin,novaexchange/EAC,IlfirinCano/shavercoin,brightcoin/brightcoin,coinkeeper/anoncoin_20150330_fixes,Ziftr/litecoin,DrCrypto/darkcoin,mooncoin-project/mooncoin-landann,Dajackal/Ronpaulcoin,bootycoin-project/bootycoin,saydulk/Feathercoin,Litecoindark/LTCD,alexandrcoin/vertcoin,Rav3nPL/doubloons-08,CrimeaCoin/crimeacoin,zemrys/vertcoin,cqtenq/Feathercoin,privatecoin/privatecoin,cryptcoins/cryptcoin,okinc/litecoin,qreatora/worldcoin-v0.8,Tetcoin/tetcoin,degenorate/Deftcoin,netswift/vertcoin,degenorate/Deftcoin,earthcoinproject/earthcoin,collapsedev/circlecash,icook/vertcoin,bitgoldcoin-project/bitgoldcoin,Tetcoin/tetcoin,brightcoin/brightcoin,cryptcoins/cryptcoin,Electronic-Gulden-Foundation/egulden,ohac/sha1coin,Czarcoin/czarcoin,ghostlander/Feathercoin,richo/dongcoin,netswift/vertcoin,enlighter/Feathercoin,Checkcoin/checkcoin,kryptokredyt/ProjektZespolowyCoin,bootycoin-project/bootycoin,shapiroisme/datadollar,enlighter/Feathercoin,ghostlander/Feathercoin,okinc/litecoin,zemrys/vertcoin,coinkeeper/2015-06-22_19-13_florincoin,united-scrypt-coin-project/unitedscryptcoin,cqtenq/Feathercoin,collapsedev/circlecash,worldcoinproject/worldcoin-v0.8,jiffe/cosinecoin,Bluejudy/worldcoin,marscoin/marscoin,Electronic-Gulden-Foundation/egulden,mrtexaznl/mediterraneancoin,cqtenq/Feathercoin,IlfirinIlfirin/shavercoin,shurcoin/shurcoin,coinkeeper/2015-06-22_19-13_florincoin,IlfirinCano/shavercoin,bootycoin-project/bootycoin,wekuiz/wekoin,razor-coin/razor,Anoncoin/anoncoin,franko-org/franko,coinkeeper/2015-06-22_18-46_razor,zemrys/vertcoin,coinkeeper/2015-04-19_21-20_litecoindark,ANCompany/birdcoin-dev,qreatora/worldcoin-v0.8,kryptokredyt/ProjektZespolowyCoin,zebrains/Blotter,coinkeeper/anoncoin_20150330_fixes,shapiroisme/datadollar,plankton12345/litecoin,wekuiz/wekoin,shurcoin/shurcoin,coinkeeper/2015-06-22_19-19_worldcoin,ghostlander/Feathercoin,ronpaulcoin/ronpaulcoin,coinkeeper/2015-06-22_18-30_anoncoin,coinkeeper/2015-06-22_18-51_vertcoin,Cancercoin/Cancercoin,Bluejudy/worldcoin,nanocoins/mycoin,razor-coin/razor,neutrinofoundation/neutrino-digital-currency,gwangjin2/gwangcoin-core,brishtiteveja/sherlockholmescoin,netswift/vertcoin,collapsedev/circlecash,IlfirinCano/shavercoin,mrtexaznl/mediterraneancoin,scamcoinz/scamcoin,stamhe/litecoin,zemrys/vertcoin,KaSt/equikoin,Cancercoin/Cancercoin,ANCompany/birdcoin-dev,Rav3nPL/doubloons-08,Tetcoin/tetcoin,zzkt/solarcoin,plankton12345/litecoin,IlfirinIlfirin/shavercoin,nanocoins/mycoin,ccoin-project/ccoin,franko-org/franko,shapiroisme/datadollar,shadowoneau/ozcoin,Checkcoin/checkcoin,WorldcoinGlobal/WorldcoinLegacy,alexandrcoin/vertcoin,gwangjin2/gwangcoin-core,brishtiteveja/sherlockholmescoin,okinc/litecoin,dakk/soundcoin,oklink-dev/litecoin_block,Electronic-Gulden-Foundation/egulden,zemrys/vertcoin,wekuiz/wekoin,Checkcoin/checkcoin,KaSt/equikoin,coinkeeper/2015-06-22_18-46_razor,ccoin-project/ccoin,Anoncoin/anoncoin,Checkcoin/checkcoin,richo/dongcoin,coinkeeper/2015-06-22_19-19_worldcoin,vertcoin/eyeglass,ghostlander/Feathercoin,collapsedev/circlecash,netswift/vertcoin,ohac/sha1coin,koharjidan/litecoin,saydulk/Feathercoin,ohac/sha1coin,degenorate/Deftcoin,bitgoldcoin-project/bitgoldcoin,marscoin/marscoin,IlfirinIlfirin/shavercoin,ghostlander/Feathercoin,micryon/GPUcoin,jiffe/cosinecoin,novaexchange/EAC,KaSt/equikoin,zebrains/Blotter,tensaix2j/bananacoin,coinkeeper/2015-06-22_19-19_worldcoin,franko-org/franko,cryptcoins/cryptcoin,cqtenq/Feathercoin,qreatora/worldcoin-v0.8,earthcoinproject/earthcoin,Electronic-Gulden-Foundation/egulden,saydulk/Feathercoin,ohac/sha1coin,zebrains/Blotter,alexandrcoin/vertcoin,Ziftr/litecoin,plankton12345/litecoin,koharjidan/litecoin,jiffe/cosinecoin