The limit was mentioned in spiffs_config.h but was not checked. Fixes https://github.com/espressif/esp-idf/issues/1546
- SPIFFS_OBJ_META_LEN can be set in sdkconfig - mtime support can be enabled in sdkconfig, if META_LENGTH is sufficient - add test for mtime updates
Fixes github issues #1012 and #1013 https://github.com/espressif/esp-idf/issues/1012 https://github.com/espressif/esp-idf/issues/1013