Update postcss-loader to version 2.0.4 🚀

[greenkeeperio-bot]

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Hello lovely humans,

postcss-loader just published its new version 2.0.4.

State	Update 🚀
Dependency	postcss-loader
New version	2.0.4
Type	devDependency

This version is not covered by your current version range.

Without accepting this pull request your project will work just like it did before. There might be a bunch of new features, fixes and perf improvements that the maintainers worked on for you though.

I recommend you look into these changes and try to get onto the latest version of postcss-loader.
Given that you have a decent test suite, a passing build is a strong indicator that you can take advantage of these changes by merging the proposed change into your project. Otherwise this branch is a great starting point for you to work on the update.

Do you have any ideas how I could improve these pull requests? Did I report anything you think isn’t right?
Are you unsure about how things are supposed to work?

There is a collection of frequently asked questions and while I’m just a bot, there is a group of people who are happy to teach me new things. Let them know.

Good luck with your project ✨

You rock!

🌴

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The new version differs by 139 commits .

• cc6544e chore(release): 2.0.4
• faaeee4 fix(index): postcss.config.js not resolved correctly (options.config)
• 4f20c99 fix(index): update validation schema, better warning message
• 3963860 docs(README): add missing comma (#223)
• df0226b docs(README): add missing comma (#225)
• 6388f0b chore(release): 2.0.3
• 159b66a fix(index): don't fail on 'sourceMap: false' && emit a warning instead, when previous map found (options.sourceMap)
• fbef238 chore(release): 2.0.2
• e764761 fix(index): 'No PostCSS Config found' (options.config) (#215)
• 2192d46 docs(README): rename cssnext to postcss-cssnext (#216)
• 63f3b14 docs(README): add missing comma (#214)
• e57cd91 docs(README): add missing comas in code examples (#211)
• da378e5 chore(release): 2.0.1
• c4f0064 fix(index): 'Cannot create property prev on boolean false' (options.sourceMap)
• e586f4a chore(release): 2.0.0

There are 139 commits in total. See the full diff.