Added badge.nvs_get_str and badge.nvs_set_str, minor cleanup
Added badge.nvs_get_str and badge.nvs_set_str, minor cleanup

SHA2017-badge/micropython-esp32,SHA2017-badge/micropython-esp32,SHA2017-badge/micropython-esp32,SHA2017-badge/micropython-esp32,SHA2017-badge/micropython-esp32