Add some example shell scripts to build on Linux

examples/ping_pong/build_linux.sh

@@ -0,0 +1,15 @@
+#!/bin/sh
+#
+# Author: Benjamin Sergeant
+# Copyright (c) 2017-2018 Machine Zone, Inc. All rights reserved.
+#
+
+# 'manual' way of building. You can also use cmake.
+
+g++ --std=c++11 \
+    ../../ixwebsocket/IXSocket.cpp	\
+    ../../ixwebsocket/IXWebSocketTransport.cpp \
+    ../../ixwebsocket/IXWebSocket.cpp \
+    -I ../.. \
+    cmd_websocket_chat.cpp \
+    -o cmd_websocket_chat