Add README and releasenotes

Author: jviau

src/Client/OrchestrationServiceClientShim/README.md

@@ -4,4 +4,15 @@ Commonly used types:
 - `ShimDurableTaskClient`
 - `ShimDurableTaskClientOptions`
 
-For more information, see https://github.com/microsoft/durabletask-dotnet
+For more information, see https://github.com/microsoft/durabletask-dotnet
+
+## Getting Started
+
+``` CSharp
+HostApplicationBuilder builder = Host.CreateApplicationBuilder(args);
+
+// instantiate this using existing Microsoft.Azure.DurableTask packages.
+IOrchestrationServiceClient orchestrationServiceClient = new AzureStorageOrchestrationService(...);
+builder.Services.AddDurableTaskClient()
+    .UseOrchestrationService(orchestrationService);
+```

src/Worker/Core/README.md

@@ -5,4 +5,4 @@ Commonly used types:
 - `DurableTaskWorkerOptions`
 - `IDurableTaskWorkerBuilder`
 
-For more information, see https://github.com/microsoft/durabletask-dotnet
+For more information, see https://github.com/microsoft/durabletask-dotnet

src/Worker/OrchestrationServiceShim/README.md

@@ -0,0 +1,18 @@
+A client implementation for `Microsoft.DurableTask`. This package includes a `DurableTaskWorker` implementation for interacting with a task hub via a `DurableTask.Core.IOrchestrationService`.
+
+Commonly used types:
+- `ShimDurableTaskWorker`
+- `ShimDurableTaskWorkerOptions`
+
+For more information, see https://github.com/microsoft/durabletask-dotnet
+
+## Getting Started
+
+``` CSharp
+HostApplicationBuilder builder = Host.CreateApplicationBuilder(args);
+
+// instantiate this using existing Microsoft.Azure.DurableTask packages.
+IOrchestrationService orchestrationService = new AzureStorageOrchestrationService(...);
+builder.Services.AddDurableTaskWorker()
+    .UseOrchestrationService(orchestrationService);
+```

src/Worker/OrchestrationServiceShim/RELEASENOTES.md

@@ -0,0 +1 @@
+- Initial implementation of `ShimDurableTaskWorker`