Add year to log line

[kgreenek]

glog recently added the year to the log line. I think abeil-py should too for compatibility. It's also useful to have the year, and only adds 4 characters.

This log line:

I0308 23:47:32.089828 400441 config.cc:27] Some log message

Would change to this:

I20200308 23:47:32.089828 400441 config.cc:27] Some log message

Issue:
google/glog#516

PR:
google/glog#530

[gpshead]

We're unlikely to do this. That google/glog project is mostly unrelated to our actual internal C++ logging library other than being derived from a very old version of it and thus having a mostly compatible C++ API.

abseil-cpp may gain a logging library in the future; we aim keep abseil-py in sync with the internal logging library behavior and anything abseil-cpp does.

Changing the log line format is unlikely for compatibility reasons.

[kgreenek]

+1 for abeil-cpp open-sourcing the logging library.

Now it looks like our c++ glog logs will be different from our python absl-py logs if we update glog.