Update version to 1.9.0-dev
diff --git a/newtmgr/newtmgr.go b/newtmgr/newtmgr.go
index eeaef26..80502b5 100644
--- a/newtmgr/newtmgr.go
+++ b/newtmgr/newtmgr.go
@@ -77,7 +77,7 @@
 		ExeName:       "newtmgr",
 		ShortName:     "Newtmgr",
 		LongName:      "Apache Newtmgr",
-		VersionString: "1.8.0",
+		VersionString: "1.9.0-dev",
 		CfgFilename:   ".newtmgr.cp.json",
 	}