WIP Set compile target to java 8

[shaundmorris]

DO NOT MERGE

This PR tests compiling with Java 11 and target set to 8 for compatibility

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This change is 

[bradh]

@shaundmorris Doesn't look like that is going to work (see CI build failure). What is the problem you're trying to solve with this?

[shaundmorris]

@bradh I was trying to figure out a way to have both java 8 and 11 build and run compatibility at the same time. Was experimenting with it.

[bradh]

I thought we agreed there was no need for JDK 8 any more?

Do we need to revisit that?

[shaundmorris]

This was an experiment to see if there is an easy way to support both on the same branch. I like the idea of moving master forward with Java 11. Previous branches can still rely on 8. So I would like to release master again with 11 support if you are okay with that @bradh

[bradh]

@shaundmorris No problem with a release.

[bradh]

@shaundmorris What is the status on this PR? Are we moving forward with java 11 only?