micropython: add micropython component

components/language/micropython/docs/esp8266/tutorial/onewire.rst

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+Controlling 1-wire devices
+==========================
+
+The 1-wire bus is a serial bus that uses just a single wire for communication
+(in addition to wires for ground and power).  The DS18B20 temperature sensor
+is a very popular 1-wire device, and here we show how to use the onewire module
+to read from such a device.
+
+For the following code to work you need to have at least one DS18S20 or DS18B20 temperature
+sensor with its data line connected to GPIO12.  You must also power the sensors
+and connect a 4.7k Ohm resistor between the data pin and the power pin.  ::
+
+    import time
+    import machine
+    import onewire, ds18x20
+
+    # the device is on GPIO12
+    dat = machine.Pin(12)
+
+    # create the onewire object
+    ds = ds18x20.DS18X20(onewire.OneWire(dat))
+
+    # scan for devices on the bus
+    roms = ds.scan()
+    print('found devices:', roms)
+
+    # loop 10 times and print all temperatures
+    for i in range(10):
+        print('temperatures:', end=' ')
+        ds.convert_temp()
+        time.sleep_ms(750)
+        for rom in roms:
+            print(ds.read_temp(rom), end=' ')
+        print()
+
+Note that you must execute the ``convert_temp()`` function to initiate a
+temperature reading, then wait at least 750ms before reading the value.