Removing CSS files (by reading the `removeCombined` property)

[sp00m]

After having optimized my main module, the CSS is added by JavaScript at runtime, by appending a style tag to the head tag. This is done in the main.js output file.

The CSS files that were combined aren't used anymore, so it could be interesting to remove them automatically. Maybe the removeCombined property could be read.

[ffflabs]

I did a quick POC and it seems to work fine #206.

Perhaps we should consider some edge cases, like if a CSS file is required by more than one build target.

Also, for the removal to actually happen, the optimizer should be configured with attributes config.removeCombined = true and config.buildCSS != false.

[ischrei]

Hi,
Any update on this issue please?
I see it is opened for a while already..
Thanks!

[alundiak]

@ischrei @amenadiel @sp00m I will work on reviewing PRs, so if the issue still relevant, please let me know. And see my PR #206 comment.