Added support for signInWithCredentials

[fernandezpaco]

Just exposing the signInWithCredential method in the polymer component.

Very useful when you already have an oauth id_token.

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[fernandezpaco]

I signed it!

[googlebot]

CLAs look good, thanks!

[polinom]

I don't think you can change the name of the project or version. That will be done by person responsible for maintaining this project.

[fernandezpaco]

This changes are not part of my pull request. I need this changes to start using this component in my app. If i dont change this in the bower file i get the original component without my changes.

[bvhme]

Hey, you can use Bower's resolutions for that, enabling you to download your version fernandezpaco/polymerfire whenever it requires polymerfire.

If you keep your pull request clean it can be merged, otherwise it needs to be replicated, because this commit cannot be merged this whole pull request cannot be merged.

[fernandezpaco]

Ok, sorry. I have removed my changes from bower.json. I think is clean now, ready to be merged.

[polinom]

Now i would say, you have to clean commit history, by squashing all those commits in to one.
git rebase in help ;)

[fernandezpaco]

:) Thanks a lot for the guidance (My first pull request)

I think it is ok now

[mbleigh]

@polinom thanks for your help guiding this PR!

[mbleigh]

LGTM