First pass at WebdriverCSS Dockerfile.

[grugnog]

This is a basic Dockerfile for WebdriverCSS. There is a build on https://hub.docker.com/r/grugnog/webdrivercss if you want to try it out (docs still WIP).

I am installing the webdrivercss module as a link, rather than from the NPM repo, so that it can be used more easily to test specific revisions/forks etc that don't have an official release.

[christian-bromann]

@grugnog what's the purpose of having that Docker file in the repo? Is it only for documentation or is it required by hub.docker.com

[grugnog]

@christian-bromann sorry for delay in replying.

A Dockerfile is required for hub.docker.com to build the image - the Dockerfile does not need to be in the project repository itself (i.e. I could have created a totally separate repo with just a Dockerfile in it). However it is nice for projects to include a Dockerfile if they are willing (and dockerizing it is not a complex project involving multiple scripts/images etc), since it can then be maintained and versioned alongside the project code and it's less likely to get out of sync. If the project owner adds a build on hub.docker.com then there is an additional benefit in that people are more likely to trust the project owner, as well as simplified adoption and contribution etc.