Introducing super basic health check for cart service (#44)

* Introducing super basic health check for cart service
  - Generated C# proto implementation for grpc health check
  - Moved all C# protos to a dedicated folder
  - Implemented basic health checking to ping CartStore (which is Redis in default implementation)
  - Base plumbing for health checks

* Introducing super basic health check for cart service

- Generated C# proto implementation for grpc health check
- Moved all C# protos to a dedicated folder
- Implemented basic health checking to ping CartStore (which is Redis in default implementation)
- Base plumbing for health checks

* Changing Ping health probe to call Redis Cache Ping method

src/cartservice/HealthImpl.cs

@@ -0,0 +1,22 @@
+using System;
+using cartservice.interfaces;
+using Grpc.Health.V1;
+using StackExchange.Redis;
+using static Grpc.Health.V1.Health;
+
+namespace cartservice {
+    internal class HealthImpl : HealthBase {
+        private ICartStore dependency { get; }
+        public HealthImpl (ICartStore dependency) {
+            this.dependency = dependency;
+        }
+
+        public HealthCheckResponse Check (HealthCheckRequest request) {
+            Console.WriteLine ("Checking CartService Health");
+
+            return new HealthCheckResponse {
+                Status = dependency.Ping() ? HealthCheckResponse.Types.ServingStatus.Serving : HealthCheckResponse.Types.ServingStatus.NotServing
+            };
+        }
+    }
+}