updated to osx image 9 on Travis (#829)
updated to osx image 9 on Travis (#829)


fassadlr/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,quantumagi/StratisBitcoinFullNode,quantumagi/StratisBitcoinFullNode,fassadlr/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,Aprogiena/StratisBitcoinFullNode,stratisproject/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,stratisproject/StratisBitcoinFullNode,Aprogiena/StratisBitcoinFullNode,mikedennis/StratisBitcoinFullNode,Aprogiena/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode,Neurosploit/StratisBitcoinFullNode,bokobza/StratisBitcoinFullNode