[omniORB] A small patch to the bi-directional example

[Vladimir Panov]

The bi-directional example in its current form doesn't work.

In src/examples/bidir/bd_client.cc, main():
move the intialization of the server object reference after the creation 
of the bi-directional POA.

Also, the instructions in src/examples/bidir/README are incorrect:
a single asterisk should be inserted before "unix,tcp,bidir" in both 
serverTransportRule and clientTransportRule examples.