Updated most packages.
Added SpecificationFor.AutoFixture
Fixed tests.
Added Nimbus.Serializers.Json
Made tests user specific.
Removed SpecificationFor class library.
Removed all the individual app.config from tests
Added linked app.config instances.
Added App.Override.config to Integration tests.
Made all Facts and Message Types Immutable.
Renamed requests and command and implementd Scoped Command or Request
Removed DateTimeHelper and introduced SystemClock
Suppressed async / await warnings.
Added user join and leave room handlers
Implemented Ban User Handler.
Implemented Change Room Topic Handler.
Fixed rename failure.
Implemented Add Owner to Room Handler
Implemented Users Allowed Rooms Handler.
Implemented Close Room Handler.