Feature/ot plat rssi (#411)

* rename otPlatRadioGetNoiseFloor to otPlatRadioGetRssi

* update cli README with singleton command

examples/platforms/cc2538/radio.c

@@ -300,7 +300,7 @@ RadioPacket *otPlatRadioGetTransmitBuffer(void)
     return &sTransmitFrame;
 }
 
-int8_t otPlatRadioGetNoiseFloor(void)
+int8_t otPlatRadioGetRssi(void)
 {
     return 0;
 }

examples/platforms/posix/radio.c

@@ -423,7 +423,7 @@ RadioPacket *otPlatRadioGetTransmitBuffer(void)
     return &sTransmitFrame;
 }
 
-int8_t otPlatRadioGetNoiseFloor(void)
+int8_t otPlatRadioGetRssi(void)
 {
     return 0;
 }

include/platform/radio.h

@@ -272,9 +272,9 @@ extern void otPlatRadioTransmitDone(bool aFramePending, ThreadError aError);
 /**
  * Get the most recent RSSI measurement.
  *
- * @returns The noise floor value in dBm when the noise floor value is valid.  127 when noise floor value is invalid.
+ * @returns The RSSI in dBm when it is valid.  127 when RSSI is invalid.
  */
-int8_t otPlatRadioGetNoiseFloor(void);
+int8_t otPlatRadioGetRssi(void);
 
 /**
  * Get the radio capabilities.

src/cli/README.md

@@ -40,6 +40,7 @@ OpenThread test scripts use the CLI to execute test cases.
 * [router](#router)
 * [routerupgradethreshold](#routerupgradethreshold)
 * [scan](#scan)
+* [singleton](#singleton)
 * [state](#state)
 * [thread](#thread)
 * [version](#version)
@@ -734,6 +735,15 @@ Perform an IEEE 802.15.4 Active Scan.
 Done
 ```
 
+### singleton
+Return true when there are no other nodes in the network, otherwise return false.
+
+```bash
+> singleton
+true or false
+Done
+```
+
 ### thread start
 
 Enable Thread protocol operation and attach to a Thread network.

src/ncp/ncp_base.cpp

@@ -1264,7 +1264,7 @@ ThreadError NcpBase::GetPropertyHandler_PHY_RSSI(uint8_t header, spinel_prop_key
                SPINEL_CMD_PROP_VALUE_IS,
                key,
                SPINEL_DATATYPE_INT8_S,
-               otPlatRadioGetNoiseFloor()
+               otPlatRadioGetRssi()
            );
 }