Fix separation of loaders

[tjallingt]

Fixes #76
(also included some code style fixes as suggested by the linter)

[huan086]

It works. Thanks!
However, for this to work, output cannot be optional, so the docs needs to updated too

output: path to write the generated css. If not provided, you'll need to listen to the 'css stream' event on the bundle to get the output.

[joeybaker]

FWIW, output is optional so that you can get the output as a stream instead of a file. It would be great if the solution worked for both of these use-cases.

[tjallingt]

As far as I can tell it doesn't change the functionality when not given a cssOutFilename as it will just store the loader the same as before. This fix only changes the functionality of the code when presented with multiple different cssOutFilenames....

[joeybaker]

cool beans.

[joshwnj]

Thanks for these updates @tjallingt , and for being patient while I got some time to review :)

[joshwnj]

published v0.17.0