Add I2SInOut library

Author: relic-se

.gitmodules

@@ -475,3 +475,6 @@
 [submodule "libraries/drivers/mhz19"]
 	path = libraries/drivers/mhz19
 	url = https://github.com/bablokb/circuitpython-mhz19.git
+[submodule "libraries/drivers/i2sinout"]
+	path = libraries/drivers/i2sinout
+	url = https://github.com/relic-se/CircuitPython_I2SInOut.git

circuitpython_community_library_list.md

@@ -68,6 +68,7 @@ Here is a listing of current CircuitPython Community Libraries. These libraries
 * [Electronutlabs CircuitPython LIS2DH12](https://github.com/electronut/Electronutlabs_CircuitPython_LIS2DH12.git) Circuitpython library for LIS2DH12 3-axis low power accelerometer. \([Docs](https://circuitpython-lis2dh12-library.readthedocs.io/en/latest/))
 * [Electronutlabs CircuitPython LTR329ALS01](https://github.com/electronut/Electronutlabs_CircuitPython_LTR329ALS01.git) Circuitpython library for reading data from light sensor LTR329ALS01. \([Docs](https://circuitpython-ltr329als01-library.readthedocs.io/en/latest/))
 * [Hierophect Circuitpython Dynamixel](https://github.com/hierophect/Hierophect_Circuitpython_Dynamixel.git) Circuitpython driver library for the Dynamixel series of servo motors from Robotis \([Docs](https://circuitpython-dynamixel.readthedocs.io/))
+* [I2SInOut](https://github.com/relic-se/CircuitPython_I2SInOut.git) CircuitPython library to handle bidirectional I2S communication to be used with audio codecs and I2S microphones \([Docs](https://circuitpython-i2sinout.readthedocs.io/))
 * [M5Stack 8 Angle and 8 Encoder Unit](https://github.com/Neradoc/CircuitPython_m5stack_unit8) Circuitpython driver library for the M5Stack 8Unit Angle and Encoder breakout boards \([Docs](https://m5stack-unit8-for-circuitpython.readthedocs.io/))
 * [MH-Z19x](https://github.com/bablokb/circuitpython-mhz19.git) Driver for the MH-Z19x CO2-sensors
 * [Mindwidgets CircuitPython DF1201S](https://github.com/mindwidgets/Mindwidgets_CircuitPython_DF1201S) CircuitPython driver for DFRobot DFPlayer Pro MP3 player with onboard storage \([Docs](https://mindwidgets-circuitpython-df1201s-library.readthedocs.io/en/latest/))