- File might not eval to false if opened with write/append and SD is gone
- Allow card to be formatted if FAT partition was not found
- Mark card as gone in certain situations
- Fix several logic errors in low level SD API
SPIFFS causes crashes if you attempt to rmdir. Since there are no true directories in spiffs, this ought to be a noop. It looks like @me-no-dev worked around this by using unlink instead of rmdir, which works in fatfs and doesn't panic spiffs. This behavior is not universal. In order to get littlefs working, it would be good to get this back to conformity. Rather than digging deep into the upstream spiffs, I just check the mountpoint and noop if it is "/spiffs". So, if the user has changed the mountpoint, this will not work, but I think it's a pretty good tradeoff.
