First Implementation of MediatR Samples

[JuergenRB]

Request Handler....................................................Y
Void Request Handler...............................................Y
Pipeline Behavior..................................................Y
Pre-Processor......................................................N
Post-Processor.....................................................N
Constrained Post-Processor.........................................N
Ordered Behaviors..................................................N
Notification Handler...............................................Y
Notification Handlers..............................................Y
Constrained Notification Handler...................................Y