modify espnow example See merge request idf/esp-idf!3144
Convenience function to fill a buffer with random bytes. Add some unit tests (only sanity checks, really.)
This change adds a check for compatibility between the nvs version found on nvs flash and the one assumed by running code during nvs initialization. Any mismatch is reported to the user using new error code ESP_ERR_NVS_NEW_VERSION_FOUND.
