redirect npm install stdout to /dev/null to avoid reaching max buffer…

… values of child_process.exec

api/core/module/module.install.js

@@ -51,7 +51,7 @@ function gitClone(url, path){
  * NPM install a specific directory
  */
 function npmInstall(path){
-    return exec(`npm install --prefix ${path}`);
+    return exec(`npm install --prefix ${path} > /dev/null`);
 }
 
 /**