CircleCI config and deploy scripts

[jakubfiala]

In this PR we

• add a circle.yml
• create a deploy.sh script to upload the dist folder to S3
• change routing to static files so that they're served from the site root
• put clean-dist in a separate sh file and add a static files symlinking step

[jakubfiala]

@alfraser86 yep, it's eu-west-2 a.k.a Ireland