Use module-specific logger in library code instead of root logger

[majiang]

This pull request is to comply with Advanced Logging Tutorial:

A good convention to use when naming loggers is to use a module-level logger, in each module which uses logging, named as follows:

logger = logging.getLogger(__name__)

This pull request is also almost identical to #94 which I'm not sure why was closed.

[delewis13]

+1 on this, using this module is adding a stream handler to my root level logger, which subsequently causes all my logging statements in the rest of my application to output multiple lines.

[majiang]

Hi Splunk team, do you have any comments, thoughts or ideas about failing CI?

[RCoff]

I definitely need this. The logs from 'binding.py' are unnecessary for me and only serve to clog up my Splunk index.

[ashah-splunk]

@majiang as per your suggestion, we have added module specific logger along with an utility to enable loggers for different levels as well. Please refer the README. The changes are available in the latest release 1.6.19

[majiang]

Thanks! It's #437, for reference