Adding common result struct
Shifting to root pkg
Merge pull request #206 from jamiehannaford/common-result

Adding common result struct
Add initial top-level acceptance tests
Rename v2_0 and add remaining boilerplate
Rename and refactor tests to use common service logic
Adding ListAPIVersions operation
Fixes to client setup and build tags
Adding API resource operation
Adding get extension operation
Adding get network operation
Adding create network operation
Making return types more consistent :boom:
Adding tests for delete network
Refactoring tests to use helper funcs :ok_hand:
Moving extensions and API versions into different sub-packages; fixing test helper methods
Shuffled resources into sub-packages and upgraded to new pagination idiom
Moving network v2 to new(est) pagination idiom
Starting subnets
Adding list and get operations for subnets