[openib-general] an example to use of multicast messages over the verbs exists in the openib svn

[Dotan Barak]

Hi all.

In 
https://openib.org/svn/trunk/contrib/mellanox/ibtp/gen2/userspace/useraccess/multicast_test 
there is
an example for using multicast messages over the verbs.

This test (for now) don't send any join message to the SA, it only 
attach (and detach) the QP to the multicast group.

Dotan