json based spec for implementors to use

Three files are provided:

1) fixtures.json

Defines the data that servers must load to test reading and updating.

2) read.json

Provides reading use cases.
Each use case is composed of config, expectedRequest and expectedResponse
config defines which fixture should be used, and other server settings
like if the server ask for client-ids, uses url based style and/or
compounds related objects.

3) write.json

Similar to read.json