Support logging to stdout

[onmomo]

As we learned the log_config.conf is gone to configure easylogging++ log FORMAT and to log to stdout.
-> #2167

* GLOBAL:
        FORMAT                  =   {"timestamp\":\"%datetime{%Y-%M-%dT%H:%m:%s.%gZ}\",\"level\":\"%level\",\"logger\":\"%logger\",\"thread\":\"%thread\",\"message\":\"%msg\"}
        FILENAME                =   "/var/milvus/logs/milvus-%datetime{%H:%m}-global.log"
        ENABLED                 =   true
        TO_FILE                 =   false
        TO_STANDARD_OUTPUT      =   true

Could you provide us with instructions on how to do so with the new logging configuration?
As we understood, only these options are supported:

logs:
      level: info
      trace.enable: false
      path: /var/lib/milvus/logs
      max_log_file_size: 1024MB
      log_rotate_num: 1

[shengjun1985]

I am sorry that the feature is not supported in the current version.

[onmomo]

Ok, that's a pity. Is there a possibility to log everything to stdout / console? This would make our life much easier again to collect the Milvus container logs with our log aggregator system.

[wxyucs]

@onmomo Good idea. We will add a configuration to make it possible.

[wxyucs]

Done