Reorganized source tree. Moved client.cpp into cmd/synergy as

synergy.cpp and server.cpp into cmd/synergyd as synergyd.cpp.
Moved and renamed related files.  Moved remaining source files
into lib/....  Modified and added makefiles as appropriate.
Result is that library files are under lib with each library
in its own directory and program files are under cmd with each
command in its own directory.

lib/io/XIO.cpp

@@ -0,0 +1,50 @@
+#include "XIO.h"
+
+//
+// XIOErrno
+//
+
+XIOErrno::XIOErrno() :
+	MXErrno()
+{
+	// do nothing
+}
+
+XIOErrno::XIOErrno(int err) :
+	MXErrno(err)
+{
+	// do nothing
+}
+
+
+//
+// XIOClose
+//
+
+CString
+XIOClose::getWhat() const throw()
+{
+	return format("XIOClose", "close: %{1}", XIOErrno::getErrstr());
+}
+
+
+//
+// XIOClosed
+//
+
+CString
+XIOClosed::getWhat() const throw()
+{
+	return format("XIOClosed", "already closed");
+}
+
+
+//
+// XIOEndOfStream
+//
+
+CString
+XIOEndOfStream::getWhat() const throw()
+{
+	return format("XIOEndOfStream", "reached end of stream");
+}