Merge pull request #34 from waltaskew/feature/logging-out

In which we slap a logout button on the app page
Merge pull request #35 from waltaskew/feature/cloudfront-upload-urls

In which we store the CloudFront URL of user-uploaded assets rather than the S3 URL
Merge pull request #36 from waltaskew/feature/more-e2e-quest-tests

In which we add thorough end-to-end tests