Fix newt to display correct version

Signed-off-by: Fabio Utzig <utzig@apache.org>
diff --git a/newt/newtutil/newtutil.go b/newt/newtutil/newtutil.go
index 9ccf7bc..f68bb18 100644
--- a/newt/newtutil/newtutil.go
+++ b/newt/newtutil/newtutil.go
@@ -36,7 +36,7 @@
 )
 
 var NewtVersion Version = Version{1, 3, 0}
-var NewtVersionStr string = "Apache Newt version: 1.3.0-dev"
+var NewtVersionStr string = "Apache Newt version: 1.3.0"
 var NewtBlinkyTag string = "mynewt_1_3_0_tag"
 var NewtNumJobs int
 var NewtForce bool