most of those are either made in the spirit of unix where one tool does one thing
- gulp and grunt are for handling multiple js scripts and all your folders of js scripts, makefile stuff
- ill assume webpack is for minimizing js
- bower and npm are package managers, while npm is just node modules, bower can do some cool stuff like install jquery or bootstrap into your local public_html folder
- es6/ecmascript is a standardized featureset of javascript that people are working on. you can use it now, but you have to install babeljs, and use expirimental option in chrome
there is yeoman.io and yo that sets up skeletons for the dev environment
there are 'base fiddles' ex 'react base fiddle' that can get you going. there is also bower and docker vm images with skeleton projects. also there is a lot of skeleton projects on github.
(its ez to breakdown a base fiddle and see whats needed to get the dev going)