Fix node selection in NodeGroup when AllowSameGroup is true, Add WellKnownGroupSelectors
Fix node selection in NodeGroup when AllowSameGroup is true, Add WellKnownGroupSelectors

dangershony/NStratis,MetacoSA/NBitcoin,NicolasDorier/NBitcoin,MetacoSA/NBitcoin,thepunctuatedhorizon/BrickCoinAlpha.0.0.1,stratisproject/NStratis,lontivero/NBitcoin