* Process rercursive folder for spiffs images
* Flat file name from the directory structure
* change method to find '/' as the suggestion of @sheinz
* remove unused variable
* Allow changing write function of stdout.
Required for stdout redirection.
Works on blocks, not chars - does _not_ use sdk_os_putc !
Should work even when linking with SPIFFS.
Fix sdk_system_rtc_mem_write and sdk_system_rtc_mem_read,
the functions did not use the user-provided offsets to rtc_mem.
Without using offset, rboot's rtcdata access, and its
temp_rom handling were broken.
Also code for sdk_cnx_sta_leave, although disabled due to accessing static date, but it shows a reference to the netif->flags and the NETIF_FLAG_DHCP flag removed in lwip v2.
Function sdk_eagle_auth_done accesses the netif-flags and the NETIF_FLAG_DHCP flag removed in lwip v2, and also the netif->ip_addr so is needed for lwip development.
Function sdk_wpa_config_bss accesses the netif->hwaddr.
Also code for a few other trivial functions that help debug the dhcpc paths.
* bmp280 more options
add option to user for temp oversampling and possibility to skipp a specific measure
* Update bmp280.h
* quick fix oups
* less redundant terms
The function sdk_wifi_station_start is one of two paths that allocates a lwip struct netif and also accesses the netif->hwaddr slot so this is required for lwip development.
Also code for sdk_wifi_station_stop and sdk_sta_status_set to better understand the status state.
Add source code for functions touching the struct netif to better support lwip development: sdk_wifi_get_ip_info, sdk_wifi_set_ip_info, sdk_wifi_get_macaddr, sdk_wifi_set_macaddr.
Also code for sdk_wifi_station_get_connect_status.
Also code for wifi_get_sleep_type and set_sleep_type, noting wifi_set_sleep_type returns a bool success flag, and implement wifi_get_sleep_type using sdk_pm_get_sleep_type.
