Add a new POSIX-specific chat client showing how to use the

posix::stream_descriptor class.


[SVN r49483]

libs/asio

@@ -1 +1 @@
-Subproject commit 96fcff70f25a2e3e69e5691c2df82c8152811f21
+Subproject commit 0b5c6d9a2ba58ab92e35410bb692bc16f9d86668