Move Google Analytics tracking code to head element.

[ghost]

This is the suggested location by Google for the Google Analytics
tracking code: https://support.google.com/analytics/answer/1008080

Also it is needed for easy site ownership verification in Google Search
Console: https://support.google.com/webmasters/answer/35179

[highergroundstudio]

Actually if you read the link you posted it says that it should be right after the closing head tag. Secondly, I would suggest changing to the async version too:

{{ template "_internal/google_analytics_async.html" . }}

[ryanfox1985]

@highergroundstudio you are right. I will close this PR and I created an issue #213 related with google async.