Upgrade to Go1.6, use vendor

Also make sure we're using a more recent version of godep

vendor/github.com/jessevdk/go-flags/termsize_nosysioctl.go

@@ -0,0 +1,7 @@
+// +build windows plan9 solaris
+
+package flags
+
+func getTerminalColumns() int {
+	return 80
+}