Installing browserify should not update package.json

npm changed their behavior of 'npm install'. See
https://github.com/npm/npm/issues/17010

use --no-save option to avoid package.json changes

scripts/fetch-language-data.sh

@@ -23,7 +23,7 @@ then
 else (
 	echo "Installing browserify"
 	cd "$BASEDIR";
-	npm install browserify
+	npm install --no-save browserify
 ) fi
 
 echo "Transforming language-data"