Report "No handlers could be found for logger 'ray.worker' when importing ray

[xutianming]

System information

• OS Platform and Distribution (e.g., Linux Ubuntu 16.04): Linux CentOS 7
• Ray installed from (source or binary): source, latest master
• Ray version:0.6.0
• Python version: Anaconda Python 2.7.15
• Exact command to reproduce: import ray

Describe the problem

Ray reports "No handlers could be found for logger 'ray.worker' " when importing ray.

More error messages are printed when calling "ray.init(use_raylet=True)"

Source code / logs

An recent pull request #3415 moved setproctitle to ray[debug] and setproctitle is not installed by default.

Without setproctitle installed, the warning message on #L79 should be printed. But logger has not been correctly configured using logging.basicConfig.

[ericl]

How about we change it to a print() then?

IMO we should consider switching to a more sane logging module such as https://pypi.org/project/glog/.

[xutianming]

@ericl I made a pull request #3483
We can move any logger.warn calls after calling logging.basicConfig for now.
Glog seems great. Current logging is kind of messy and setting 'configure_logging=False' might lead to more error messages.