Tacker/api-datamodel

= ServiceVM/DeviceManager API/Data model = Designing API/Data Model The discussion is done at google-doc for now. https://docs.google.com/document/d/10v818QsHWw5lSpiCMfh908PAvVzkw7_ZUL0cgDiH3Vk/edit?usp=sharing

Once we have stackforge repo, we'll switch to gerrit.