Add option to disable compression of cached files

[kganser]

I'm submitting a feature request

Webpack Version:
1.10.x/2.x

Babel Core Version:
6.x

Babel Loader Version:
5.4.x/6.2.x

Please tell us about your environment:
OSX 10.x / Linux / Windows 10

Current behavior:
All cached files are gzipped.

Expected/desired behavior:
Would like an option to disable gzipping of cached files for improved load speed.

This should be fairly simple to implement. I was able to bypass compression locally by just commenting out some lines in fs-cache.js, but I figured that this would be a nice config option in general.

Thanks,
Klaus

[loganfsmyth]

This should be fixed with #574