Merge pull request #237 from siddacious/ds1841

adding DS1841

Author: ladyada

.gitmodules

@@ -661,3 +661,6 @@
 [submodule "libraries/drivers/rockblock"]
 	path = libraries/drivers/rockblock
 	url = https://github.com/adafruit/Adafruit_CircuitPython_RockBlock.git
+[submodule "libraries/drivers/ds1841"]
+	path = libraries/drivers/ds1841
+	url = https://github.com/adafruit/Adafruit_CircuitPython_DS1841.git

docs/drivers.rst

@@ -425,6 +425,7 @@ Miscellaneous
     BD3491FS Audio Processor  <https://circuitpython.readthedocs.io/projects/bd3491fs/en/latest/>
     CAP1188 8-Key Capacitive Touch <https://circuitpython.readthedocs.io/projects/cap1188/en/latest/>
     DRV2605 Haptic Motor Controller <https://circuitpython.readthedocs.io/projects/drv2605/en/latest/>
+    DS1841 I2C Logarithmic Potentiometer <https://adafruit-circuitpython-ds1841.readthedocs.io/en/latest/>
     DS3502 I2C Potentiometer <https://circuitpython.readthedocs.io/projects/ds3502/en/latest/>
     Fingerprint Sensor <https://circuitpython.readthedocs.io/projects/fingerprint/en/latest/>
     FRAM Non-Volatile Memory <https://circuitpython.readthedocs.io/projects/fram/en/latest/>