Make publishable as a gem. #80

Add the necessary files to make publishable as a gem.  This is maybe a little kludgy and I don't know if tehre's a better way to do it: because the original fork has the files laid out differently than rails gems, need, in the .gemspec file I create the needed folders and copy the js & css to them.  There's no way to clean that up, though, but I have added those to the .gitignore. Fixes #80.