Based on SDK20_Native_160106D

190313A   1.Add Signals: SIG_AT_IAP2_START_LOCATION_INFO
                         SIG_AT_IAP2_STOP_LOCATION_INFO
                         SIG_AT_IAP2_UPDATE_LOCATION_INFO.
          2.Add function: AT_IAP2_UpdateLocationInformation(). Updata location information when SIG_AT_IAP2_UPDATE_LOCATION_INFO arrives.
