[docs] add release note for change to GBT
[docs] add release note for change to GBT

GBT must now be called with the segwit rule.

afk11/bitcoin,jambolo/bitcoin,FeatherCoin/Feathercoin,dscotese/bitcoin,ahmedbodi/vertcoin,instagibbs/bitcoin,vertcoin/vertcoin,gjhiggins/vcoincore,sipsorcery/bitcoin,jtimon/bitcoin,bitcoinsSG/bitcoin,namecoin/namecore,tecnovert/particl-core,AkioNak/bitcoin,practicalswift/bitcoin,ajtowns/bitcoin,myriadcoin/myriadcoin,MeshCollider/bitcoin,bespike/litecoin,sstone/bitcoin,Sjors/bitcoin,achow101/bitcoin,namecoin/namecoin-core,litecoin-project/litecoin,n1bor/bitcoin,droark/bitcoin,instagibbs/bitcoin,lateminer/bitcoin,achow101/bitcoin,pstratem/bitcoin,myriadteam/myriadcoin,yenliangl/bitcoin,domob1812/bitcoin,cdecker/bitcoin,fujicoin/fujicoin,alecalve/bitcoin,namecoin/namecoin-core,EthanHeilman/bitcoin,particl/particl-core,ajtowns/bitcoin,jnewbery/bitcoin,OmniLayer/omnicore,nikkitan/bitcoin,DigitalPandacoin/pandacoin,lateminer/bitcoin,mm-s/bitcoin,CryptArc/bitcoin,droark/bitcoin,fujicoin/fujicoin,cdecker/bitcoin,GroestlCoin/bitcoin,kallewoof/bitcoin,bitcoin/bitcoin,alecalve/bitcoin,MarcoFalke/bitcoin,yenliangl/bitcoin,vertcoin/vertcoin,fanquake/bitcoin,n1bor/bitcoin,MarcoFalke/bitcoin,alecalve/bitcoin,rnicoll/bitcoin,ajtowns/bitcoin,r8921039/bitcoin,andreaskern/bitcoin,dscotese/bitcoin,nikkitan/bitcoin,EthanHeilman/bitcoin,jtimon/bitcoin,litecoin-project/litecoin,ElementsProject/elements,jamesob/bitcoin,sipsorcery/bitcoin,bespike/litecoin,mruddy/bitcoin,fujicoin/fujicoin,ajtowns/bitcoin,Xekyo/bitcoin,practicalswift/bitcoin,ajtowns/bitcoin,tjps/bitcoin,bitcoin/bitcoin,monacoinproject/monacoin,myriadteam/myriadcoin,achow101/bitcoin,bitcoinknots/bitcoin,bitcoinknots/bitcoin,CryptArc/bitcoin,qtumproject/qtum,dscotese/bitcoin,jambolo/bitcoin,mm-s/bitcoin,pataquets/namecoin-core,andreaskern/bitcoin,rnicoll/bitcoin,JeremyRubin/bitcoin,sstone/bitcoin,vertcoin/vertcoin,bespike/litecoin,qtumproject/qtum,Sjors/bitcoin,gjhiggins/vcoincore,ahmedbodi/vertcoin,fujicoin/fujicoin,GroestlCoin/GroestlCoin,CryptArc/bitcoin,Sjors/bitcoin,ElementsProject/elements,r8921039/bitcoin,mitchellcash/bitcoin,AkioNak/bitcoin,droark/bitcoin,GroestlCoin/bitcoin,DigitalPandacoin/pandacoin,pstratem/bitcoin,AkioNak/bitcoin,domob1812/bitcoin,jamesob/bitcoin,myriadteam/myriadcoin,vertcoin/vertcoin,andreaskern/bitcoin,MeshCollider/bitcoin,rnicoll/dogecoin,bitcoinsSG/bitcoin,apoelstra/bitcoin,n1bor/bitcoin,midnightmagic/bitcoin,OmniLayer/omnicore,jamesob/bitcoin,peercoin/peercoin,pataquets/namecoin-core,andreaskern/bitcoin,lateminer/bitcoin,mruddy/bitcoin,GroestlCoin/bitcoin,mm-s/bitcoin,FeatherCoin/Feathercoin,pataquets/namecoin-core,bitcoinsSG/bitcoin,monacoinproject/monacoin,tecnovert/particl-core,instagibbs/bitcoin,afk11/bitcoin,peercoin/peercoin,yenliangl/bitcoin,qtumproject/qtum,yenliangl/bitcoin,vertcoin/vertcoin,qtumproject/qtum,jonasschnelli/bitcoin,EthanHeilman/bitcoin,peercoin/peercoin,jnewbery/bitcoin,jambolo/bitcoin,DigitalPandacoin/pandacoin,monacoinproject/monacoin,untrustbank/litecoin,prusnak/bitcoin,jonasschnelli/bitcoin,untrustbank/litecoin,practicalswift/bitcoin,wellenreiter01/Feathercoin,ajtowns/bitcoin,midnightmagic/bitcoin,mruddy/bitcoin,monacoinproject/monacoin,MeshCollider/bitcoin,prusnak/bitcoin,midnightmagic/bitcoin,ahmedbodi/vertcoin,anditto/bitcoin,r8921039/bitcoin,jamesob/bitcoin,bitcoin/bitcoin,sstone/bitcoin,peercoin/peercoin,bitcoin/bitcoin,JeremyRubin/bitcoin,namecoin/namecoin-core,domob1812/namecore,nikkitan/bitcoin,n1bor/bitcoin,bitcoinknots/bitcoin,mruddy/bitcoin,tjps/bitcoin,kallewoof/bitcoin,dscotese/bitcoin,CryptArc/bitcoin,pataquets/namecoin-core,tecnovert/particl-core,kallewoof/bitcoin,jlopp/statoshi,cdecker/bitcoin,FeatherCoin/Feathercoin,GroestlCoin/GroestlCoin,fanquake/bitcoin,prusnak/bitcoin,domob1812/namecore,namecoin/namecore,ElementsProject/elements,myriadteam/myriadcoin,yenliangl/bitcoin,lateminer/bitcoin,anditto/bitcoin,bespike/litecoin,MarcoFalke/bitcoin,particl/particl-core,particl/particl-core,pstratem/bitcoin,andreaskern/bitcoin,rnicoll/bitcoin,FeatherCoin/Feathercoin,pataquets/namecoin-core,pstratem/bitcoin,midnightmagic/bitcoin,mitchellcash/bitcoin,bitcoinknots/bitcoin,lateminer/bitcoin,FeatherCoin/Feathercoin,myriadcoin/myriadcoin,rnicoll/dogecoin,JeremyRubin/bitcoin,jonasschnelli/bitcoin,pataquets/namecoin-core,Sjors/bitcoin,droark/bitcoin,AkioNak/bitcoin,prusnak/bitcoin,Xekyo/bitcoin,jonasschnelli/bitcoin,peercoin/peercoin,fanquake/bitcoin,myriadcoin/myriadcoin,Xekyo/bitcoin,GroestlCoin/bitcoin,tecnovert/particl-core,DigitalPandacoin/pandacoin,jamesob/bitcoin,GroestlCoin/bitcoin,nikkitan/bitcoin,practicalswift/bitcoin,r8921039/bitcoin,lateminer/bitcoin,jtimon/bitcoin,andreaskern/bitcoin,tjps/bitcoin,ElementsProject/elements,kallewoof/bitcoin,practicalswift/bitcoin,prusnak/bitcoin,cdecker/bitcoin,tjps/bitcoin,dscotese/bitcoin,untrustbank/litecoin,myriadcoin/myriadcoin,monacoinproject/monacoin,JeremyRubin/bitcoin,mm-s/bitcoin,jamesob/bitcoin,DigitalPandacoin/pandacoin,jlopp/statoshi,apoelstra/bitcoin,midnightmagic/bitcoin,qtumproject/qtum,namecoin/namecoin-core,wellenreiter01/Feathercoin,peercoin/peercoin,OmniLayer/omnicore,instagibbs/bitcoin,EthanHeilman/bitcoin,gjhiggins/vcoincore,namecoin/namecore,jtimon/bitcoin,sstone/bitcoin,MeshCollider/bitcoin,bitcoinknots/bitcoin,mm-s/bitcoin,sipsorcery/bitcoin,myriadteam/myriadcoin,sipsorcery/bitcoin,particl/particl-core,domob1812/bitcoin,Sjors/bitcoin,wellenreiter01/Feathercoin,Xekyo/bitcoin,sipsorcery/bitcoin,rnicoll/bitcoin,jnewbery/bitcoin,DigitalPandacoin/pandacoin,EthanHeilman/bitcoin,afk11/bitcoin,ahmedbodi/vertcoin,tecnovert/particl-core,achow101/bitcoin,wellenreiter01/Feathercoin,rnicoll/dogecoin,gjhiggins/vcoincore,myriadcoin/myriadcoin,ahmedbodi/vertcoin,tjps/bitcoin,mitchellcash/bitcoin,mitchellcash/bitcoin,jambolo/bitcoin,fanquake/bitcoin,apoelstra/bitcoin,FeatherCoin/Feathercoin,afk11/bitcoin,jtimon/bitcoin,MeshCollider/bitcoin,mm-s/bitcoin,anditto/bitcoin,rnicoll/dogecoin,domob1812/namecore,namecoin/namecore,litecoin-project/litecoin,instagibbs/bitcoin,bespike/litecoin,wellenreiter01/Feathercoin,jambolo/bitcoin,MarcoFalke/bitcoin,bitcoin/bitcoin,alecalve/bitcoin,bitcoinsSG/bitcoin,AkioNak/bitcoin,kallewoof/bitcoin,OmniLayer/omnicore,namecoin/namecore,n1bor/bitcoin,EthanHeilman/bitcoin,mruddy/bitcoin,jnewbery/bitcoin,alecalve/bitcoin,cdecker/bitcoin,vertcoin/vertcoin,r8921039/bitcoin,namecoin/namecoin-core,jlopp/statoshi,domob1812/bitcoin,domob1812/namecore,untrustbank/litecoin,GroestlCoin/GroestlCoin,jambolo/bitcoin,untrustbank/litecoin,mruddy/bitcoin,MarcoFalke/bitcoin,rnicoll/bitcoin,bitcoin/bitcoin,JeremyRubin/bitcoin,afk11/bitcoin,achow101/bitcoin,dscotese/bitcoin,particl/particl-core,Xekyo/bitcoin,afk11/bitcoin,practicalswift/bitcoin,rnicoll/dogecoin,jnewbery/bitcoin,anditto/bitcoin,tjps/bitcoin,myriadcoin/myriadcoin,r8921039/bitcoin,nikkitan/bitcoin,GroestlCoin/bitcoin,droark/bitcoin,CryptArc/bitcoin,cdecker/bitcoin,jlopp/statoshi,litecoin-project/litecoin,rnicoll/bitcoin,domob1812/namecore,GroestlCoin/GroestlCoin,bitcoinsSG/bitcoin,midnightmagic/bitcoin,namecoin/namecoin-core,anditto/bitcoin,pstratem/bitcoin,GroestlCoin/GroestlCoin,fanquake/bitcoin,domob1812/namecore,qtumproject/qtum,ElementsProject/elements,apoelstra/bitcoin,kallewoof/bitcoin,sstone/bitcoin,bitcoinsSG/bitcoin,mitchellcash/bitcoin,anditto/bitcoin,sstone/bitcoin,jlopp/statoshi,n1bor/bitcoin,domob1812/bitcoin,alecalve/bitcoin,domob1812/bitcoin,litecoin-project/litecoin,jonasschnelli/bitcoin,CryptArc/bitcoin,fujicoin/fujicoin,myriadteam/myriadcoin,droark/bitcoin,gjhiggins/vcoincore,monacoinproject/monacoin,MarcoFalke/bitcoin,namecoin/namecore,prusnak/bitcoin,OmniLayer/omnicore,achow101/bitcoin,wellenreiter01/Feathercoin,ahmedbodi/vertcoin,untrustbank/litecoin,AkioNak/bitcoin,apoelstra/bitcoin,pstratem/bitcoin,particl/particl-core,litecoin-project/litecoin,ElementsProject/elements,GroestlCoin/GroestlCoin,instagibbs/bitcoin,fujicoin/fujicoin,bespike/litecoin,sipsorcery/bitcoin,tecnovert/particl-core,jtimon/bitcoin,yenliangl/bitcoin,fanquake/bitcoin,apoelstra/bitcoin,nikkitan/bitcoin,JeremyRubin/bitcoin,Xekyo/bitcoin,qtumproject/qtum,OmniLayer/omnicore,gjhiggins/vcoincore,jlopp/statoshi,MeshCollider/bitcoin,mitchellcash/bitcoin