To use gproc to register names using the 'via' mechanism that was
recently added to OTP (gen_server, gen_fsm, gen_event) it must provide a
send/2 function with the following type spec:
send(Name :: term(), Msg :: term()) -> pid().
Currently gproc:send/2 returns the message that was sent. This patch
changes it so that the new type spec for it is:
send(Name :: term(), Msg :: term()) -> pid() | [pid()].
It will now return the pid or list of pids the message was sent to.