Small cleanup in demos (#572)

samples/gtk/src/Main.kt

@@ -28,24 +28,23 @@ fun <F : CFunction<*>> g_signal_connect(obj: CPointer<*>, actionName: String,
 fun activate(app: CPointer<GtkApplication>?, user_data: gpointer?) {
     val windowWidget = gtk_application_window_new(app)!!
     val window = windowWidget.reinterpret<GtkWindow>()
-    gtk_window_set_title(window, "Window");
+    gtk_window_set_title(window, "Window")
     gtk_window_set_default_size(window, 200, 200)
 
     val button_box = gtk_button_box_new(
             GtkOrientation.GTK_ORIENTATION_HORIZONTAL)!!
-    gtk_container_add(window.reinterpret(), button_box);
+    gtk_container_add(window.reinterpret(), button_box)
 
     val button = gtk_button_new_with_label("Konan говорит: click me!")!!
     g_signal_connect(button, "clicked",
-            staticCFunction { widget: CPointer<GtkApplication>?, data: gpointer? ->
-                println("Hi Kotlin")
-            });
+            staticCFunction { _: CPointer<GtkWidget>?, _: gpointer? -> println("Hi Kotlin")
+            })
     g_signal_connect(button, "clicked",
             staticCFunction { widget: CPointer<GtkWidget>? ->
                 gtk_widget_destroy(widget)
             },
             window, G_CONNECT_SWAPPED)
-    gtk_container_add (button_box.reinterpret(), button);
+    gtk_container_add (button_box.reinterpret(), button)
 
     gtk_widget_show_all(windowWidget)
 }

samples/nonBlockingEchoServer/EchoServer.kt

@@ -194,13 +194,7 @@ fun acceptClientsAndRun(serverFd: Int, block: suspend Client.() -> Unit) {
     }
 }
 
-class IOException: RuntimeException {
-    constructor() : super() {
-    }
-
-    constructor(message: String): super(message) {
-    }
-}
+class IOException(message: String): RuntimeException(message)
 
 val errno: Int
     get() = interop_errno()

samples/nonBlockingEchoServer/README.md

@@ -19,11 +19,14 @@ Run the server:
 
     ./EchoServer.kexe 3000 &
 
-Test the server by conecting to it, for example with telnet:
+Test the server by connecting to it, for example with telnet:
 
     telnet localhost 3000
 
 Write something to console and watch server echoing it back.
+Concurrently connect from another terminal. Note that each connection gets its own
+connection id prefixed to echo response.
+
 
 ~~Quit telnet by pressing ctrl+] ctrl+D~~