Update polymer-bundler to the latest version 🚀

[greenkeeper[bot]]

Version 4.0.0 of polymer-bundler was just published.

Dependency	polymer-bundler
Current Version	3.1.1
Type	dependency

The version 4.0.0 is not covered by your current version range.

If you don’t accept this pull request, your project will work just like it did before. However, you might be missing out on a bunch of new features, fixes and/or performance improvements from the dependency update.

It might be worth looking into these changes and trying to get this project onto the latest version of polymer-bundler.

If you have a solid test suite and good coverage, a passing build is a strong indicator that you can take advantage of these changes directly by merging the proposed change into your project. If the build fails or you don’t have such unconditional trust in your tests, this branch is a great starting point for you to work on the update.

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Your Greenkeeper bot :palm_tree:

[greenkeeper[bot]]

Version 4.0.1 just got published.

Update to this version instead 🚀

[greenkeeper[bot]]

Version 4.0.2 just got published.

Update to this version instead 🚀

[greenkeeper[bot]]

• The dependency polymer-bundler was updated from 3.1.1 to 4.0.3.

Update to this version instead 🚀

[greenkeeper[bot]]

• The dependency polymer-bundler was updated from 3.1.1 to 4.0.4.

Update to this version instead 🚀

[greenkeeper[bot]]

• The dependency polymer-bundler was updated from 3.1.1 to 4.0.5.

Update to this version instead 🚀