Add script to call webpack to deploy and watch frontend code from within flask.  Optimize script location (#236)

* Add script to call webpack to deploy and watch frontend code from within flask.  Optimize script location

* remove npm install

* Create "setup_dev_env.sh" script that will set up all the node and SDK depenencies.  Create "start_dev_server.sh" to start up dev server, which will start backend server and start webpack --watch on frontend.

* scalars frontend basically done

* frontend rename common/fun to util

* add images, scalar config

* add expandpael arrow

* fix scalars tooltip display problem

commit eb6d0cce
Author: superjom <superjom@gmail.com>
Date:   Mon Dec 25 19:48:28 2017 +0800

    code format

commit 353e1028
Author: superjom <superjom@gmail.com>
Date:   Mon Dec 25 19:47:46 2017 +0800

    restore

* scalars frontend basically done

* frontend rename common/fun to util