Update README.md

Author: shaoziyang

sensor/README.md

@@ -1,12 +1,15 @@
 # Sensor-libs
 
 
+* [APDS9930 Digital Proximity and Ambient Light Sensor](APDS9930)
 * [BMP180 Digital pressure sensor drive](bmp180) **(recommend replace with BMP280)**
 * [BMP280 Digital pressure sensor drive](bmp280)
 * [BME280 humidity and pressure sensor drive](bme280)
-* [APDS9930 Digital Proximity and Ambient Light Sensor](APDS9930)
+* [MMC5603 3-axis Magnetic Sensor](MMC5603)
+* [SC7A20 3-AXIS ACCELEROMETER SENSOR](SC7A20)
 * [SHT20 Humidity and Temperature Sensor](sht20)
 * [SHT3x Humidity and Temperature Sensor](SHT3x)
+* [si7051 Temperature Sensor](si7051)
 * [ST HTS221 humidity and temperature sensor](HTS221)
 * [ST LPS22 pressure sensor](LPS22)
 * [ST STTS751 temperature sensor](STTS751)