Changed setup documentation to add jQuery and CSS and image files.

Summary

Provide a general description of the code changes in your pull request.

Please double-check that:

• All changes were made in CoffeeScript files, not JavaScript files.
• You used Grunt to build the JavaScript files and tested them locally.
• You've updated both the jQuery and Prototype versions.
• You haven't manually updated the version number in package.json.
• If necessary, you've updated the documentation.

See the Pull Requests section of our Contributing Guidelines for more details.

References

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