Big cleanup on Google Compute Service

  * Remove complexity around location by using aggregate apis, which removes custom location module
  * reduce chattiness and confusion in createNode by consolidating network requests
  * switch to uris as ids, which removes the InstanceInZone and MachineTypeInZone class
  * start using MWS, which makes it possible to read the offline tests for compute service
  * reduced newlines needed in tests by switching mock project name to "party"

I used this test to see what the heck we actually do, vs clicking through a bunch of files. Using this test, I've already taken out the need for a few network calls.