Google universal tracking

[jousby]

Google Analytics has two options for tracking websites now. The legacy system which is now called 'classic' and the new system called 'universal tracking' which is in beta. This pull request adds support for the new universal tracking script and adds 'google_classic' and 'google_universal' as options in the providers section of the config file.

[bzz]

Thank you for contributing!
+1 for merging this one as this still keeps classic code and adds new universal one.
Is there anything to be done to merge\close it?

[marshallshen]

@jousby , thanks for the PR!

[sapzildj]

+1

[groundh0g]

This was a PR against the jb-development branch, which ideally would be host to our features until merging into master. Unfortunately, the merge didn't have the desired effect.

Looks like the analytics stub is also in the master branch (as googleUA via PR #228), but not referenced in the analytics include or in the _config.yml. Should be a trivial matter to incorporate the edits from this PR along with #228.

I didn't realize the plumbing was disconnected earlier. Thanks for bringing attention to this.

Since both source PRs are closed, I created issue #282 to track.