fix(template-webpack): use css-loader instead of file-loader

[shimaore]

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Summarize your changes:

Instead of relying on the style-loader/url/file-loader pipeline, we use the style-loader/css-loader pipeline. This means the CSS ends up embedded in the JavaScript code generated by webpack, but it appears to work better.

[malept]

Just one change, otherwise this looks good.

[shimaore]

Right, not removing file-loader was pure lazyness on my part, didn't want to check the remainder of the template in case it was used somewhere else… it wasn't.