[7.1.1] don't overwrite log4j2.properties with 6.x non-JSON version

[abraxxa]

Elasticsearch version: 7.1.1

Role version: 7.1.1

JVM version (java -version): bundled JDK

OS version (uname -a if on a Unix-like system): Linux hostname 4.18.0-18-generic #19~18.04.1-Ubuntu SMP Fri Apr 5 10:22:13 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux

Description of the problem including expected versus actual behaviour:
The template file templates/log4j2.properties.j2 shipped with the role is from version 6 and logs in plain text and not JSON.
We would prefer an option to not overwrite the file installed by the package at all, for example by setting es_config_log4j2: null.

[Crazybus]

The template file templates/log4j2.properties.j2 shipped with the role is from version 6 and logs in plain text and not JSON.

I think it might even be from version 5 looking at how old the commit messages are :o

We can just remove it altogether and instead give the user an option to replace the logging config. I believe this was being manually added via a template back when this role supported running multiple instances at the same time.

[jmlrt]

@abraxxa, we just merged #637 which stop overwriting log4j2.properties among other things.

[abraxxa]

Thanks for the information, I can confirm that this works as expected.