Update checkBIP0030 to not use deprecated function.
Update checkBIP0030 to not use deprecated function.

Rather than using the deprecated TxShas function on a btcutil.Block,
convert the checkBIP0030 to use the newer preferred method of ranging over
the Transactions to obtain the cached hash of each transaction.

This is also a little more efficient since it can avoid creating and
caching an extra slice to keep the hashes in addition to having the hash
cached with each transaction.

jrick/dcrd,dan-da/btcd,BitGo/prova,toddfries/btcd,glv2/ppcd,BitGo/prova,decred/dcrd,tb00/btcd,stevenroose/btcd,aakselrod/btcd,soapboxsys/ombfullnode,soapboxsys/ombfullnode,qchain/btcd,cqswxj2013/btcd,jrick/btcd,jcmincke/dcrd,mathiasrw/btcd,hectorj/btcd,ppcsuite/ppcd-old,aakselrod/btcd,Cleawing/btcd,ltcsuite/ltcd,Dirbaio/btcd,DanielKrawisz/btcd,adiabat/btcd,dajohi/btcd,adiabat/btcd,qchain/btcd,cqswxj2013/btcd,Roasbeef/btcd,jcmincke/dcrd,dajohi/btcd,cjepson/btcd,danoctavian/btcd,btcsuitereleases/btcd,glv2/ppcd,ppcsuite/ppcd-old,1d4Nf6/btcd,pkothbauer/btcd,Dirbaio/btcd,CryptocurrencyCabal/htcd,davecgh/btcd,Roasbeef/btcd,mathiasrw/btcd,ppcsuite/ppcd,btcsuite/btcd,DanielKrawisz/btcd,decred/dcrd,Stash-Crypto/btcd,dan-da/btcd,davecgh/btcd,1d4Nf6/btcd,jongillham/btcd,jongillham/btcd,ltcsuite/ltcd,FactomProject/btcd,Dirbaio/btcd,Stash-Crypto/btcd,danoctavian/btcd,jrick/btcd,btcsuite/btcd,FactomProject/btcd,stevenroose/btcd,jcmincke/dcrd,Cleawing/btcd,ppcsuite/ppcd,btcsuitereleases/btcd,jrick/dcrd,sysbot/btcd,tb00/btcd,runeaune/btcd,jimmysong/btcd,CryptocurrencyCabal/htcd,sysbot/btcd,jimmysong/btcd,hectorj/btcd,runeaune/btcd,cjepson/btcd,jrick/btcd,wallclockbuilder/btcd,pkothbauer/btcd,dajohi/btcd,wallclockbuilder/btcd,toddfries/btcd