add minimal java.net.Socket implementation to support Socket.setTcpNoDelay

classpath/java/net/SocketException.java

@@ -0,0 +1,23 @@
+/* Copyright (c) 2008, Avian Contributors
+
+   Permission to use, copy, modify, and/or distribute this software
+   for any purpose with or without fee is hereby granted, provided
+   that the above copyright notice and this permission notice appear
+   in all copies.
+
+   There is NO WARRANTY for this software.  See license.txt for
+   details. */
+
+package java.net;
+
+import java.io.IOException;
+
+public class SocketException extends IOException {
+  public SocketException(String message) {
+    super(message);
+  }
+
+  public SocketException() {
+    this(null);
+  }
+}