[#1409] Signal changes in log configuration.


Problem description
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When changing the log options, we want to reconfigure the logger,


Changes description
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Add signal notification for file, syslog and windows_eventlog

Add changes listeners for file, syslog and windows_eventlog. When settings are changes, the logger will automatically try to reconfigure.

The tests were cleaned so that all _Logger related tests are inside TestLogger suite, and Handler specific tests are in separate suites.


How to try and test the changes
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reviewers @alibotean @bnickname 

Check that changes make sense.