* Add webpack as an option
Adds webpack as a js_taskrunner option to cookiecutter-json. Will clone @hzdg/cookiecutter-webpack --pydanny-django branch into the project using cookiecutter's api in post_hooks.
The static webpack project will be placed into the <project_slug>/static/<project_slug>/ directory.
The webpack configs are placed in the ./config/ directory.
The cookiecutter-webpack project includes react / redux / karma configurations that are brought into the project.
* Add webpack documentation
