Batch processing?

[justinanastos]

We're using purgecss in our postcss configuration. Our purgecss takes a ~3 seconds to run. This plugin will run that 3 second task on each individual file. I think it would make more sense to concatenate all the css files to a single ast and then process that with postcss. My tests show that it would take 3 seconds for ALL the files instead of per file.