A warning log is already emitted if eve-log is enabled in the
configuration but json support is not built so the logger
registration functions can be silent.
As the logging modules are no longer threading modules, rename
them so they don't look like they are being registered as
threading modules.
Also, move the registration to the output.c which will handle
registration of the loggers.
When the string representation of a JSON message grew bigger than
64k, the JSON record would just be truncated. This lead to errors
in the parser(s) of the JSON stream.
This patch changes the buffer logic to grow the buffer on demand.
Use proper LogFileCtx and MemBuffer handling so we can have multiple
loggers active at the same time.
Change 'date' field to timestamp, and use ISO notation to make it
the same as the other JSON outputs.