* Updated preferences.rst
* Added into FAQ info about SPIFFS failed mount
* Updated troubleshooting
* Moved SPIFFS paragraph from FAQ to troubleshooting
* Minor updates
* Updated troubleshooting
* Updated SD README files and example comments
* Updated troubleshooting with SD issue
* Added note about S3 pins
* Updated SDMMC test setPins calls + added definition for default pins
* Updated SD_MMC comments
* Added pin table to SD_MMC readme
* Updated table in SD_SPI
* Updated based on comments
* Update io_mux.rst
* Update README.md