PostCSS concatenator is not hashing files

[kepta]

I believe this is a bug since PostCSS concatenator earlier used to accept hash parameter, but in the latest code hashing functionality is missing.

[davidtheclark]

This was intentional, because we decided the concatenator function itself would be cleaner if it didn't have to worry about that; instead, a separate processing step could take the file, hash it, and rename it.

You can go with whatever you think is best.

[kepta]

This is no longer valid as we are using Webpack for css loading.