Setup CI

[DennisSchwartz]

We need a continuous integration setup that allows deployment of the site when a pull request is merged.

Examples: TravisCI, CodeShip, CircleCI.

Some of those offer free accounts for open source project or a low number of deployments.

[jayjayjpg]

Biojs.net is currently automatically rebuilt and deployed if the build was successful once a new PR has been merged to the master branch. Still this is a great issue, as we haven't got any tests for biojs.net yet and it would be great to have a small test suite setup at least that can be run with e.g. Travis