Adds restart server API to client library

src/Tgstation.Server.Client/AdministrationClient.cs

@@ -27,5 +27,8 @@ namespace Tgstation.Server.Client
 
 		/// <inheritdoc />
 		public Task Update(Administration administration, CancellationToken cancellationToken) => apiClient.Update(Routes.Administration, administration, cancellationToken);
+
+		/// <inheritdoc />
+		public Task Restart(CancellationToken cancellationToken) => apiClient.Delete(Routes.Administration, cancellationToken);
 	}
 }

src/Tgstation.Server.Client/IAdministrationClient.cs

@@ -23,5 +23,12 @@ namespace Tgstation.Server.Client
 		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
 		/// <returns>A <see cref="Task"/> representing the running operation</returns>
 		Task Update(Administration administration, CancellationToken cancellationToken);
+
+		/// <summary>
+		/// Restarts the TGS server
+		/// </summary>
+		/// <param name="cancellationToken">The <see cref="CancellationToken"/> for the operation</param>
+		/// <returns>A <see cref="Task"/> representing the running operation</returns>
+		Task Restart(CancellationToken cancellationToken);
 	}
 }