EMANE events not restricted to localhost lo device

```
Two instances of CORE running on the same network will interfere with each
other. To generate location events, CORE uses libemaneeventservice.

The library documentation says:
* The default values are: group 224.1.2.8, port 45703, multicast loop
enabled (1), TTL 32. No default multicast device is specified. The
kernel routing table is used.

Even if the device is set to lo, the events will leak out usually due to the
host's default route. CORE should consider the OTA manager device and Event
service device set in the EMANE global config, and add an appropriate multicast
route for the configured interface.

```

Original issue reported on code.google.com by `ahrenh...@gmail.com` on 9 May 2011 at 6:50