Move eslint, stylelint, jest config to dot-config files

I'm hoping to move toward using more standard "dot config file" approach for eslint, stylelint, and jest configuration. I think the biggest benefit of this change is that our text editors will now be able to automatically format-on-save.

This work is started on this branch: https://github.com/infielddigital/aem-webpack-example/tree/feature/update-eslint-configuartion-strategy