Update slip-radio readme
-This project is intended to run on a mode that is connected to a native host system
-by SLIP. The SLIP is really SERIAL LINE 15.4, as this just turns the mote into a smart
-radio, running the RPL and 6lowpan stack on the Host. This goes with native-border-router.
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+This example is intended to run on a mode that is connected to a native host
+system by SLIP. Full IEEE 802.15.4 packets are transmitted over slip, turning
+the mote into a simple radio, with the RPL and 6LoWPAN stack running on the
+host. This is typically used with the native border router (example
+`rpl-border-router` on target native).
