Cleaner Google Analytics Code and upgrade to Awestruct 0.5.5

Hey @hferentschik can you review that one quickly?

I also merged `rake setup` and `rake setup[local]` to always behave as if it was `rake setup[local]`.
The global mode is error prone and can pollute the global system and I don't see a huge avantage to use it even in prod.
finally a new version available via rubygems