Replace log4j logger with slf4j in java files

[odpi]

Replace log4j logger with slf4j in java files

[planetf1]

Do we need to go anything in the build to reduce the chance of including the circular log4j/slf adapter relationship?

Would something like the rules for maven enforcer at https://tenmilesquare.com/utilizing-maven-enforcer-plugin-to-ensure-dependency-and-version-usage/ help add this validation in one place, and avoid errors downstream in our poms?

Additionally #22 is a change in how we express our own dependencies, which can affect transitive dependency resolution?

[planetf1]

One proposal - make the slf change, and then add this enforcement if we see it appear again and find it helps prevent the error. If not leave as is?