Separated app into three layers, cleaned up leftovers

Birdmap.BLL/Startup.cs

@@ -0,0 +1,17 @@
+using Birdmap.BLL.Interfaces;
+using Birdmap.BLL.Services;
+using Microsoft.Extensions.Configuration;
+using Microsoft.Extensions.DependencyInjection;
+
+namespace Birdmap.BLL
+{
+    public static class Startup
+    {
+        public static IServiceCollection ConfigureBLL(this IServiceCollection services, IConfiguration configuration)
+        {
+            services.AddTransient<IAuthService, AuthService>();
+
+            return services;
+        }
+    }
+}