Added relic_usb_host_gamepad library

Author: relic-se

.gitmodules

@@ -502,3 +502,6 @@
 [submodule "libraries/drivers/at42qt2120"]
 	path = libraries/drivers/at42qt2120
 	url = https://github.com/MikeCoats/CircuitPython_AT42QT2120.git
+[submodule "libraries/helpers/usb_host_gamepad"]
+	path = libraries/helpers/usb_host_gamepad
+	url = https://github.com/relic-se/CircuitPython_USB_Host_Gamepad.git

circuitpython_community_library_list.md

@@ -155,6 +155,7 @@ c* [CircuitPython_RotarySelect](https://github.com/FoamyGuy/CircuitPython_Rotary
 * [CircuitPython TZDB](https://github.com/evindunn/circuitpython_tzdb) IANA timezones for adafruit_datetime ([PyPi](https://pypi.org/project/circuitpython-tzdb/)) \([Docs](https://circuitpython-tzdb.readthedocs.io/en/latest/))
 * [CircuitPython uplot](https://github.com/jposada202020/CircuitPython_uplot) Plot library for CircuitPython ([PyPi](https://pypi.org/project/circuitpython-uplot/)) \([Docs](https://circuitpython-uplot.readthedocs.io/en/latest/))
 * [CircuitPython_USB_Host_Descriptor_Parser](https://github.com/relic-se/CircuitPython_USB_Host_Descriptor_Parser) Helper to parse USB descriptors \([Docs](https://circuitpython-usb-host-descriptor-parser.readthedocs.io/en/latest/))
+* [CircuitPython_USB_Host_Gamepad](https://github.com/relic-se/CircuitPython_USB_Host_Gamepad) Helper to connect with and read compatible USB gamepad devices \([Docs](https://circuitpython-usb-host-gamepad.readthedocs.io/en/latest/))
 * [CircuitPython_WaveBuilder](https://github.com/CedarGroveStudios/CircuitPython_WaveBuilder.git) A CircuitPython class to construct a composite synthio wave table from a collection of oscillators. \([Docs](https://github.com/CedarGroveStudios/CircuitPython_WaveBuilder/blob/main/media/pseudo_rtd_cedargrove_wavebuilder.pdf))
 * [CircuitPython_Waveform](https://github.com/relic-se/CircuitPython_Waveform.git) Helper library to generate simple and composite waveforms for use with synthio. \([Docs](https://circuitpython-waveform.readthedocs.io/))
 * [CircuitPython_WaveViz](https://github.com/CedarGroveStudios/CircuitPython_WaveViz.git) A CircuitPython class to create a positionable displayio.Group graphics widget from a synthio wave table. \([Docs](https://github.com/CedarGroveStudios/CircuitPython_WaveViz/blob/main/media/pseudo_rtd_cedargrove_waveviz.pdf))