test: Generate one block for each send in wallet_import_rescan
test: Generate one block for each send in wallet_import_rescan

This ...
* ensures that enough coins are available/spendable, even when more
  variants are added
* ensures that all mempool txs are mined, even when more variants are
  added
* makes the test more specific to test that the confirmation height
  is properly reported and timestamps are correctly handled in the test
  logic
* prepares the test for a future, where blocks are skipped for rescan if
  they are deemed irrelevant by a filter (c.f. BIP157)

vertcoin/vertcoin,pataquets/namecoin-core,litecoin-project/litecoin,domob1812/namecore,anditto/bitcoin,namecoin/namecoin-core,andreaskern/bitcoin,jlopp/statoshi,n1bor/bitcoin,peercoin/peercoin,namecoin/namecore,nikkitan/bitcoin,JeremyRubin/bitcoin,Xekyo/bitcoin,midnightmagic/bitcoin,Xekyo/bitcoin,cdecker/bitcoin,litecoin-project/litecoin,fujicoin/fujicoin,pstratem/bitcoin,tecnovert/particl-core,EthanHeilman/bitcoin,ElementsProject/elements,instagibbs/bitcoin,MarcoFalke/bitcoin,JeremyRubin/bitcoin,peercoin/peercoin,mruddy/bitcoin,ElementsProject/elements,domob1812/bitcoin,nikkitan/bitcoin,fanquake/bitcoin,achow101/bitcoin,namecoin/namecore,ajtowns/bitcoin,cdecker/bitcoin,pstratem/bitcoin,ahmedbodi/vertcoin,andreaskern/bitcoin,mm-s/bitcoin,AkioNak/bitcoin,CryptArc/bitcoin,peercoin/peercoin,ahmedbodi/vertcoin,tecnovert/particl-core,rnicoll/bitcoin,namecoin/namecore,bitcoin/bitcoin,domob1812/bitcoin,cdecker/bitcoin,kallewoof/bitcoin,instagibbs/bitcoin,pataquets/namecoin-core,domob1812/namecore,domob1812/bitcoin,tjps/bitcoin,MarcoFalke/bitcoin,bitcoinsSG/bitcoin,qtumproject/qtum,EthanHeilman/bitcoin,GroestlCoin/bitcoin,jamesob/bitcoin,litecoin-project/litecoin,gjhiggins/vcoincore,apoelstra/bitcoin,JeremyRubin/bitcoin,namecoin/namecoin-core,rnicoll/dogecoin,wellenreiter01/Feathercoin,Sjors/bitcoin,rnicoll/bitcoin,jamesob/bitcoin,ajtowns/bitcoin,vertcoin/vertcoin,alecalve/bitcoin,bitcoin/bitcoin,andreaskern/bitcoin,instagibbs/bitcoin,apoelstra/bitcoin,sipsorcery/bitcoin,achow101/bitcoin,kallewoof/bitcoin,AkioNak/bitcoin,practicalswift/bitcoin,nikkitan/bitcoin,practicalswift/bitcoin,peercoin/peercoin,jtimon/bitcoin,FeatherCoin/Feathercoin,Xekyo/bitcoin,anditto/bitcoin,anditto/bitcoin,monacoinproject/monacoin,GroestlCoin/bitcoin,monacoinproject/monacoin,rnicoll/bitcoin,bitcoinsSG/bitcoin,dscotese/bitcoin,lateminer/bitcoin,bitcoinsSG/bitcoin,anditto/bitcoin,mm-s/bitcoin,sipsorcery/bitcoin,AkioNak/bitcoin,jnewbery/bitcoin,rnicoll/bitcoin,jamesob/bitcoin,mruddy/bitcoin,mruddy/bitcoin,apoelstra/bitcoin,MarcoFalke/bitcoin,cdecker/bitcoin,yenliangl/bitcoin,instagibbs/bitcoin,tecnovert/particl-core,FeatherCoin/Feathercoin,practicalswift/bitcoin,litecoin-project/litecoin,Sjors/bitcoin,CryptArc/bitcoin,rnicoll/dogecoin,sipsorcery/bitcoin,gjhiggins/vcoincore,jtimon/bitcoin,vertcoin/vertcoin,prusnak/bitcoin,andreaskern/bitcoin,pstratem/bitcoin,sstone/bitcoin,prusnak/bitcoin,domob1812/namecore,andreaskern/bitcoin,fujicoin/fujicoin,fanquake/bitcoin,vertcoin/vertcoin,jtimon/bitcoin,qtumproject/qtum,sipsorcery/bitcoin,pstratem/bitcoin,fanquake/bitcoin,mruddy/bitcoin,bitcoin/bitcoin,MeshCollider/bitcoin,DigitalPandacoin/pandacoin,jambolo/bitcoin,MeshCollider/bitcoin,GroestlCoin/GroestlCoin,bitcoinsSG/bitcoin,DigitalPandacoin/pandacoin,fujicoin/fujicoin,alecalve/bitcoin,GroestlCoin/bitcoin,JeremyRubin/bitcoin,prusnak/bitcoin,cdecker/bitcoin,nikkitan/bitcoin,AkioNak/bitcoin,qtumproject/qtum,nikkitan/bitcoin,namecoin/namecoin-core,tjps/bitcoin,DigitalPandacoin/pandacoin,ajtowns/bitcoin,mitchellcash/bitcoin,ajtowns/bitcoin,jnewbery/bitcoin,midnightmagic/bitcoin,qtumproject/qtum,gjhiggins/vcoincore,alecalve/bitcoin,rnicoll/dogecoin,EthanHeilman/bitcoin,bitcoinknots/bitcoin,litecoin-project/litecoin,particl/particl-core,bitcoin/bitcoin,gjhiggins/vcoincore,ahmedbodi/vertcoin,achow101/bitcoin,fanquake/bitcoin,particl/particl-core,tjps/bitcoin,bitcoinsSG/bitcoin,anditto/bitcoin,nikkitan/bitcoin,tecnovert/particl-core,anditto/bitcoin,pstratem/bitcoin,bitcoinknots/bitcoin,namecoin/namecore,MeshCollider/bitcoin,namecoin/namecoin-core,mruddy/bitcoin,domob1812/bitcoin,bitcoinknots/bitcoin,lateminer/bitcoin,Sjors/bitcoin,alecalve/bitcoin,jonasschnelli/bitcoin,gjhiggins/vcoincore,mruddy/bitcoin,yenliangl/bitcoin,domob1812/namecore,kallewoof/bitcoin,jonasschnelli/bitcoin,tecnovert/particl-core,particl/particl-core,qtumproject/qtum,monacoinproject/monacoin,sstone/bitcoin,peercoin/peercoin,FeatherCoin/Feathercoin,jambolo/bitcoin,domob1812/namecore,practicalswift/bitcoin,GroestlCoin/GroestlCoin,tjps/bitcoin,jambolo/bitcoin,jnewbery/bitcoin,bitcoin/bitcoin,yenliangl/bitcoin,mitchellcash/bitcoin,ElementsProject/elements,jtimon/bitcoin,wellenreiter01/Feathercoin,jambolo/bitcoin,rnicoll/dogecoin,vertcoin/vertcoin,domob1812/bitcoin,pataquets/namecoin-core,jamesob/bitcoin,midnightmagic/bitcoin,midnightmagic/bitcoin,fanquake/bitcoin,ahmedbodi/vertcoin,dscotese/bitcoin,GroestlCoin/bitcoin,GroestlCoin/GroestlCoin,FeatherCoin/Feathercoin,jlopp/statoshi,rnicoll/bitcoin,particl/particl-core,alecalve/bitcoin,lateminer/bitcoin,jtimon/bitcoin,ElementsProject/elements,lateminer/bitcoin,fujicoin/fujicoin,Sjors/bitcoin,wellenreiter01/Feathercoin,CryptArc/bitcoin,AkioNak/bitcoin,EthanHeilman/bitcoin,ElementsProject/elements,prusnak/bitcoin,ahmedbodi/vertcoin,sstone/bitcoin,MarcoFalke/bitcoin,sipsorcery/bitcoin,MeshCollider/bitcoin,gjhiggins/vcoincore,Xekyo/bitcoin,Sjors/bitcoin,jonasschnelli/bitcoin,sipsorcery/bitcoin,DigitalPandacoin/pandacoin,sstone/bitcoin,achow101/bitcoin,prusnak/bitcoin,bitcoinsSG/bitcoin,pataquets/namecoin-core,wellenreiter01/Feathercoin,cdecker/bitcoin,Xekyo/bitcoin,vertcoin/vertcoin,jtimon/bitcoin,domob1812/namecore,MeshCollider/bitcoin,fanquake/bitcoin,jambolo/bitcoin,mitchellcash/bitcoin,jnewbery/bitcoin,particl/particl-core,wellenreiter01/Feathercoin,practicalswift/bitcoin,Xekyo/bitcoin,alecalve/bitcoin,instagibbs/bitcoin,ajtowns/bitcoin,litecoin-project/litecoin,monacoinproject/monacoin,instagibbs/bitcoin,namecoin/namecoin-core,bitcoinknots/bitcoin,tecnovert/particl-core,pstratem/bitcoin,MarcoFalke/bitcoin,GroestlCoin/bitcoin,kallewoof/bitcoin,CryptArc/bitcoin,n1bor/bitcoin,kallewoof/bitcoin,mm-s/bitcoin,fujicoin/fujicoin,dscotese/bitcoin,namecoin/namecore,rnicoll/bitcoin,namecoin/namecoin-core,n1bor/bitcoin,MeshCollider/bitcoin,FeatherCoin/Feathercoin,prusnak/bitcoin,jnewbery/bitcoin,mitchellcash/bitcoin,CryptArc/bitcoin,rnicoll/dogecoin,mitchellcash/bitcoin,qtumproject/qtum,lateminer/bitcoin,tjps/bitcoin,mm-s/bitcoin,n1bor/bitcoin,FeatherCoin/Feathercoin,tjps/bitcoin,EthanHeilman/bitcoin,ajtowns/bitcoin,fujicoin/fujicoin,andreaskern/bitcoin,qtumproject/qtum,yenliangl/bitcoin,monacoinproject/monacoin,DigitalPandacoin/pandacoin,sstone/bitcoin,ElementsProject/elements,sstone/bitcoin,GroestlCoin/GroestlCoin,EthanHeilman/bitcoin,achow101/bitcoin,pataquets/namecoin-core,jamesob/bitcoin,apoelstra/bitcoin,mm-s/bitcoin,GroestlCoin/GroestlCoin,jlopp/statoshi,kallewoof/bitcoin,jlopp/statoshi,particl/particl-core,pataquets/namecoin-core,jlopp/statoshi,n1bor/bitcoin,yenliangl/bitcoin,midnightmagic/bitcoin,CryptArc/bitcoin,peercoin/peercoin,AkioNak/bitcoin,ahmedbodi/vertcoin,achow101/bitcoin,GroestlCoin/bitcoin,mm-s/bitcoin,lateminer/bitcoin,bitcoin/bitcoin,dscotese/bitcoin,yenliangl/bitcoin,jonasschnelli/bitcoin,domob1812/bitcoin,dscotese/bitcoin,MarcoFalke/bitcoin,midnightmagic/bitcoin,DigitalPandacoin/pandacoin,namecoin/namecore,jlopp/statoshi,jamesob/bitcoin,jambolo/bitcoin,apoelstra/bitcoin,JeremyRubin/bitcoin,GroestlCoin/GroestlCoin,practicalswift/bitcoin,jonasschnelli/bitcoin,n1bor/bitcoin,apoelstra/bitcoin,dscotese/bitcoin,JeremyRubin/bitcoin,wellenreiter01/Feathercoin,bitcoinknots/bitcoin,monacoinproject/monacoin,mitchellcash/bitcoin