Support for .min.js files

The sanity bot raises issues for minified files as for normal js files. Some rules probably need to be relaxed, like e.g. the need for a space after a flow control statement keyword - for minified files, we want to avoid this so that the resultant artifact is of minimal size.

We could also add a warning / message saying that the author of such an upload should also commit the sources / scripts that took part in generating the file.