Helper class for log buffer
BUFFER_OFF
Disable buffering (buffer becomes a mere wrapper)
BUFFER_INFINITE
Disable auto flush feature
BUFFER_SIZE_DEFAULT
Default buffer size
CALLBACK_FLUSH_EACH
Callback: Flush iteration (content objects)
CALLBACK_LOG_BEFORE
Callback: Log method, before (logger object)
CALLBACK_LOG_AFTER
Callback: Log method, after (logger object)