Double WDS client in the next branch

[alecmev]

webpack-dev-server, when invoked via CLI, has the inline mode enabled by default, which means that webpack-dev-server/client?${domain} is added to the entry automatically, regardless of whether there is one already or not. I've opened an issue about it + there is an older one, but, until then, consider switching back to the Node API version of WDS, or disabling the inline mode (a side effect of which is a [kind of] incorrect "Project is running at").

#27 is still relevant.