Introduce token issuing.
Merge branch 'master' of https://github.com/DimensionDataCBUSydney/CaaS.OpenStack-Facade

Conflicts:
	src/Caas.OpenStack.API/Controllers/IdentityController.cs
Login token
Merge branch 'master' of https://github.com/DimensionDataCBUSydney/CaaS.OpenStack-Facade

Conflicts:
	src/Caas.OpenStack.API/Middleware/CaaSAuthenticationMiddleWare.cs