[scripts] lint-whitespace: use perl instead of grep -P
[scripts] lint-whitespace: use perl instead of grep -P

MacOS does not support 'grep -P' out of the box. This change makes
it easier for developers to check for whitespace problems locally.

bitcoinsSG/bitcoin,anditto/bitcoin,Christewart/bitcoin,Kogser/bitcoin,bitcoin/bitcoin,sipsorcery/bitcoin,midnightmagic/bitcoin,mitchellcash/bitcoin,GroestlCoin/GroestlCoin,namecoin/namecoin-core,sebrandon1/bitcoin,namecoin/namecore,wellenreiter01/Feathercoin,guncoin/guncoin,afk11/bitcoin,andreaskern/bitcoin,bitcoin/bitcoin,rnicoll/bitcoin,CryptArc/bitcoin,Bushstar/UFO-Project,tecnovert/particl-core,CryptArc/bitcoin,domob1812/namecore,MeshCollider/bitcoin,jtimon/bitcoin,lateminer/bitcoin,pataquets/namecoin-core,cdecker/bitcoin,pstratem/bitcoin,Kogser/bitcoin,anditto/bitcoin,GroestlCoin/bitcoin,JeremyRubin/bitcoin,MarcoFalke/bitcoin,ajtowns/bitcoin,pataquets/namecoin-core,n1bor/bitcoin,anditto/bitcoin,instagibbs/bitcoin,JeremyRubin/bitcoin,ahmedbodi/vertcoin,lateminer/bitcoin,GlobalBoost/GlobalBoost,mitchellcash/bitcoin,litecoin-project/litecoin,lbryio/lbrycrd,mruddy/bitcoin,sipsorcery/bitcoin,thrasher-/litecoin,sipsorcery/bitcoin,namecoin/namecoin-core,fanquake/bitcoin,fujicoin/fujicoin,Flowdalic/bitcoin,MeshCollider/bitcoin,guncoin/guncoin,pataquets/namecoin-core,domob1812/namecore,nikkitan/bitcoin,paveljanik/bitcoin,OmniLayer/omnicore,MeshCollider/bitcoin,bitcoinknots/bitcoin,ElementsProject/elements,digibyte/digibyte,JeremyRubin/bitcoin,FeatherCoin/Feathercoin,rawodb/bitcoin,myriadcoin/myriadcoin,kazcw/bitcoin,kallewoof/bitcoin,Sjors/bitcoin,ericshawlinux/bitcoin,jamesob/bitcoin,lateminer/bitcoin,sstone/bitcoin,Kogser/bitcoin,afk11/bitcoin,yenliangl/bitcoin,OmniLayer/omnicore,droark/bitcoin,namecoin/namecoin-core,Kogser/bitcoin,donaloconnor/bitcoin,JeremyRubin/bitcoin,mruddy/bitcoin,AkioNak/bitcoin,anditto/bitcoin,h4x3rotab/BTCGPU,rnicoll/bitcoin,fujicoin/fujicoin,ajtowns/bitcoin,midnightmagic/bitcoin,GroestlCoin/GroestlCoin,Kogser/bitcoin,afk11/bitcoin,EthanHeilman/bitcoin,prusnak/bitcoin,monacoinproject/monacoin,vmp32k/litecoin,ericshawlinux/bitcoin,domob1812/namecore,donaloconnor/bitcoin,mruddy/bitcoin,vertcoin/vertcoin,nikkitan/bitcoin,FeatherCoin/Feathercoin,GroestlCoin/GroestlCoin,lateminer/bitcoin,Christewart/bitcoin,jambolo/bitcoin,anditto/bitcoin,kallewoof/bitcoin,alecalve/bitcoin,randy-waterhouse/bitcoin,domob1812/namecore,tecnovert/particl-core,practicalswift/bitcoin,mm-s/bitcoin,digibyte/digibyte,ericshawlinux/bitcoin,mitchellcash/bitcoin,bespike/litecoin,RHavar/bitcoin,afk11/bitcoin,MeshCollider/bitcoin,jmcorgan/bitcoin,OmniLayer/omnicore,paveljanik/bitcoin,ahmedbodi/vertcoin,monacoinproject/monacoin,vertcoin/vertcoin,TheBlueMatt/bitcoin,rawodb/bitcoin,EthanHeilman/bitcoin,domob1812/bitcoin,domob1812/namecore,namecoin/namecoin-core,Xekyo/bitcoin,Xekyo/bitcoin,BTCGPU/BTCGPU,bespike/litecoin,vertcoin/vertcoin,paveljanik/bitcoin,gjhiggins/vcoincore,r8921039/bitcoin,untrustbank/litecoin,jamesob/bitcoin,domob1812/bitcoin,sipsorcery/bitcoin,wellenreiter01/Feathercoin,qtumproject/qtum,jambolo/bitcoin,tecnovert/particl-core,mruddy/bitcoin,Christewart/bitcoin,joshrabinowitz/bitcoin,jonasschnelli/bitcoin,Kogser/bitcoin,Flowdalic/bitcoin,paveljanik/bitcoin,mitchellcash/bitcoin,rawodb/bitcoin,particl/particl-core,rnicoll/bitcoin,yenliangl/bitcoin,GlobalBoost/GlobalBoost,Flowdalic/bitcoin,n1bor/bitcoin,randy-waterhouse/bitcoin,myriadcoin/myriadcoin,domob1812/bitcoin,tecnovert/particl-core,vertcoin/vertcoin,bespike/litecoin,GlobalBoost/GlobalBoost,n1bor/bitcoin,CryptArc/bitcoin,alecalve/bitcoin,Sjors/bitcoin,tjps/bitcoin,domob1812/bitcoin,tjps/bitcoin,particl/particl-core,vmp32k/litecoin,pataquets/namecoin-core,TheBlueMatt/bitcoin,achow101/bitcoin,h4x3rotab/BTCGPU,vmp32k/litecoin,h4x3rotab/BTCGPU,kallewoof/bitcoin,sstone/bitcoin,r8921039/bitcoin,fanquake/bitcoin,GlobalBoost/GlobalBoost,EthanHeilman/bitcoin,jonasschnelli/bitcoin,ahmedbodi/vertcoin,Bushstar/UFO-Project,kallewoof/bitcoin,BTCGPU/BTCGPU,jamesob/bitcoin,GroestlCoin/GroestlCoin,sebrandon1/bitcoin,randy-waterhouse/bitcoin,alecalve/bitcoin,prusnak/bitcoin,ElementsProject/elements,digibyte/digibyte,JeremyRubin/bitcoin,AkioNak/bitcoin,jlopp/statoshi,myriadcoin/myriadcoin,MeshCollider/bitcoin,namecoin/namecore,domob1812/huntercore,alecalve/bitcoin,CryptArc/bitcoin,jambolo/bitcoin,untrustbank/litecoin,jamesob/bitcoin,midnightmagic/bitcoin,FeatherCoin/Feathercoin,bespike/litecoin,EthanHeilman/bitcoin,qtumproject/qtum,sipsorcery/bitcoin,practicalswift/bitcoin,RHavar/bitcoin,jtimon/bitcoin,rnicoll/dogecoin,myriadteam/myriadcoin,pstratem/bitcoin,rawodb/bitcoin,joshrabinowitz/bitcoin,domob1812/huntercore,jlopp/statoshi,bespike/litecoin,rnicoll/bitcoin,mitchellcash/bitcoin,mm-s/bitcoin,jtimon/bitcoin,gjhiggins/vcoincore,jnewbery/bitcoin,myriadteam/myriadcoin,GroestlCoin/bitcoin,thrasher-/litecoin,lbryio/lbrycrd,prusnak/bitcoin,OmniLayer/omnicore,JeremyRubin/bitcoin,ajtowns/bitcoin,mm-s/bitcoin,fujicoin/fujicoin,h4x3rotab/BTCGPU,vertcoin/vertcoin,peercoin/peercoin,namecoin/namecore,Kogser/bitcoin,stamhe/bitcoin,mm-s/bitcoin,Christewart/bitcoin,achow101/bitcoin,kazcw/bitcoin,sebrandon1/bitcoin,GroestlCoin/bitcoin,yenliangl/bitcoin,Kogser/bitcoin,gjhiggins/vcoincore,midnightmagic/bitcoin,vmp32k/litecoin,Sjors/bitcoin,instagibbs/bitcoin,stamhe/bitcoin,ElementsProject/elements,CryptArc/bitcoin,TheBlueMatt/bitcoin,kazcw/bitcoin,thrasher-/litecoin,droark/bitcoin,monacoinproject/monacoin,fujicoin/fujicoin,jlopp/statoshi,sebrandon1/bitcoin,pstratem/bitcoin,ahmedbodi/vertcoin,droark/bitcoin,sstone/bitcoin,ajtowns/bitcoin,wellenreiter01/Feathercoin,bitcoinknots/bitcoin,gjhiggins/vcoincore,bitcoin/bitcoin,rawodb/bitcoin,yenliangl/bitcoin,rawodb/bitcoin,particl/particl-core,vmp32k/litecoin,prusnak/bitcoin,tjps/bitcoin,ahmedbodi/vertcoin,Flowdalic/bitcoin,TheBlueMatt/bitcoin,digibyte/digibyte,jonasschnelli/bitcoin,FeatherCoin/Feathercoin,rnicoll/dogecoin,Xekyo/bitcoin,untrustbank/litecoin,BTCGPU/BTCGPU,qtumproject/qtum,digibyte/digibyte,Kogser/bitcoin,ElementsProject/elements,tjps/bitcoin,nikkitan/bitcoin,jamesob/bitcoin,RHavar/bitcoin,particl/particl-core,donaloconnor/bitcoin,cdecker/bitcoin,andreaskern/bitcoin,jambolo/bitcoin,litecoin-project/litecoin,guncoin/guncoin,dscotese/bitcoin,afk11/bitcoin,BTCGPU/BTCGPU,qtumproject/qtum,joshrabinowitz/bitcoin,MarcoFalke/bitcoin,Xekyo/bitcoin,jambolo/bitcoin,ajtowns/bitcoin,rnicoll/bitcoin,stamhe/bitcoin,Flowdalic/bitcoin,monacoinproject/monacoin,stamhe/bitcoin,Christewart/bitcoin,kazcw/bitcoin,r8921039/bitcoin,droark/bitcoin,myriadcoin/myriadcoin,myriadteam/myriadcoin,peercoin/peercoin,Xekyo/bitcoin,rnicoll/bitcoin,myriadcoin/myriadcoin,h4x3rotab/BTCGPU,achow101/bitcoin,jnewbery/bitcoin,pstratem/bitcoin,peercoin/peercoin,OmniLayer/omnicore,RHavar/bitcoin,fanquake/bitcoin,GroestlCoin/GroestlCoin,mm-s/bitcoin,peercoin/peercoin,Bushstar/UFO-Project,thrasher-/litecoin,myriadteam/myriadcoin,achow101/bitcoin,bitcoinsSG/bitcoin,bitcoin/bitcoin,wellenreiter01/Feathercoin,paveljanik/bitcoin,untrustbank/litecoin,apoelstra/bitcoin,achow101/bitcoin,thrasher-/litecoin,namecoin/namecore,domob1812/huntercore,digibyte/digibyte,qtumproject/qtum,gjhiggins/vcoincore,untrustbank/litecoin,cdecker/bitcoin,andreaskern/bitcoin,jlopp/statoshi,domob1812/huntercore,stamhe/bitcoin,fanquake/bitcoin,untrustbank/litecoin,peercoin/peercoin,instagibbs/bitcoin,guncoin/guncoin,jamesob/bitcoin,MarcoFalke/bitcoin,ericshawlinux/bitcoin,n1bor/bitcoin,nikkitan/bitcoin,kazcw/bitcoin,DigitalPandacoin/pandacoin,prusnak/bitcoin,BTCGPU/BTCGPU,tjps/bitcoin,BTCGPU/BTCGPU,Bushstar/UFO-Project,apoelstra/bitcoin,jnewbery/bitcoin,DigitalPandacoin/pandacoin,Flowdalic/bitcoin,afk11/bitcoin,DigitalPandacoin/pandacoin,gjhiggins/vcoincore,namecoin/namecoin-core,mm-s/bitcoin,cdecker/bitcoin,nikkitan/bitcoin,randy-waterhouse/bitcoin,Bushstar/UFO-Project,dscotese/bitcoin,GlobalBoost/GlobalBoost,andreaskern/bitcoin,nikkitan/bitcoin,fujicoin/fujicoin,AkioNak/bitcoin,kallewoof/bitcoin,cdecker/bitcoin,instagibbs/bitcoin,litecoin-project/litecoin,myriadcoin/myriadcoin,tecnovert/particl-core,pstratem/bitcoin,practicalswift/bitcoin,sipsorcery/bitcoin,litecoin-project/litecoin,jtimon/bitcoin,domob1812/huntercore,rnicoll/dogecoin,thrasher-/litecoin,DigitalPandacoin/pandacoin,fanquake/bitcoin,tjps/bitcoin,bitcoinsSG/bitcoin,myriadteam/myriadcoin,randy-waterhouse/bitcoin,ElementsProject/elements,ElementsProject/elements,DigitalPandacoin/pandacoin,lbryio/lbrycrd,GroestlCoin/bitcoin,guncoin/guncoin,andreaskern/bitcoin,RHavar/bitcoin,sstone/bitcoin,jmcorgan/bitcoin,andreaskern/bitcoin,wellenreiter01/Feathercoin,apoelstra/bitcoin,RHavar/bitcoin,AkioNak/bitcoin,dscotese/bitcoin,sebrandon1/bitcoin,pataquets/namecoin-core,MarcoFalke/bitcoin,yenliangl/bitcoin,anditto/bitcoin,domob1812/huntercore,jmcorgan/bitcoin,namecoin/namecoin-core,sebrandon1/bitcoin,EthanHeilman/bitcoin,bitcoin/bitcoin,donaloconnor/bitcoin,apoelstra/bitcoin,TheBlueMatt/bitcoin,bitcoinsSG/bitcoin,bitcoin/bitcoin,cdecker/bitcoin,joshrabinowitz/bitcoin,Kogser/bitcoin,MeshCollider/bitcoin,instagibbs/bitcoin,jnewbery/bitcoin,GlobalBoost/GlobalBoost,alecalve/bitcoin,rnicoll/dogecoin,kazcw/bitcoin,MarcoFalke/bitcoin,lateminer/bitcoin,GroestlCoin/bitcoin,rnicoll/dogecoin,dscotese/bitcoin,midnightmagic/bitcoin,Kogser/bitcoin,particl/particl-core,dscotese/bitcoin,ericshawlinux/bitcoin,pataquets/namecoin-core,r8921039/bitcoin,mruddy/bitcoin,vertcoin/vertcoin,MarcoFalke/bitcoin,alecalve/bitcoin,domob1812/namecore,bespike/litecoin,mruddy/bitcoin,monacoinproject/monacoin,Christewart/bitcoin,TheBlueMatt/bitcoin,n1bor/bitcoin,peercoin/peercoin,r8921039/bitcoin,jonasschnelli/bitcoin,Sjors/bitcoin,domob1812/bitcoin,jnewbery/bitcoin,n1bor/bitcoin,EthanHeilman/bitcoin,AkioNak/bitcoin,bitcoinknots/bitcoin,namecoin/namecore,FeatherCoin/Feathercoin,particl/particl-core,ajtowns/bitcoin,lbryio/lbrycrd,ericshawlinux/bitcoin,CryptArc/bitcoin,donaloconnor/bitcoin,lbryio/lbrycrd,ahmedbodi/vertcoin,jlopp/statoshi,lbryio/lbrycrd,litecoin-project/litecoin,stamhe/bitcoin,jtimon/bitcoin,AkioNak/bitcoin,domob1812/bitcoin,myriadteam/myriadcoin,joshrabinowitz/bitcoin,qtumproject/qtum,lbryio/lbrycrd,DigitalPandacoin/pandacoin,tecnovert/particl-core,fujicoin/fujicoin,yenliangl/bitcoin,achow101/bitcoin,h4x3rotab/BTCGPU,Xekyo/bitcoin,sstone/bitcoin,Sjors/bitcoin,jlopp/statoshi,kallewoof/bitcoin,bitcoinknots/bitcoin,guncoin/guncoin,droark/bitcoin,monacoinproject/monacoin,jmcorgan/bitcoin,vmp32k/litecoin,practicalswift/bitcoin,paveljanik/bitcoin,lateminer/bitcoin,jmcorgan/bitcoin,GlobalBoost/GlobalBoost,dscotese/bitcoin,jtimon/bitcoin,namecoin/namecore,FeatherCoin/Feathercoin,mitchellcash/bitcoin,jambolo/bitcoin,donaloconnor/bitcoin,bitcoinsSG/bitcoin,practicalswift/bitcoin,wellenreiter01/Feathercoin,apoelstra/bitcoin,randy-waterhouse/bitcoin,bitcoinsSG/bitcoin,Bushstar/UFO-Project,Kogser/bitcoin,prusnak/bitcoin,GroestlCoin/GroestlCoin,litecoin-project/litecoin,instagibbs/bitcoin,r8921039/bitcoin,OmniLayer/omnicore,apoelstra/bitcoin,pstratem/bitcoin,sstone/bitcoin,practicalswift/bitcoin,fanquake/bitcoin,droark/bitcoin,qtumproject/qtum,bitcoinknots/bitcoin,jmcorgan/bitcoin,midnightmagic/bitcoin,joshrabinowitz/bitcoin,GroestlCoin/bitcoin,jonasschnelli/bitcoin