Add example to JAVA_OPTS framework documentation

Previously, the documentation for the JAVA_OPTS framework wasn't clear
enough that a user could properly configure it without help.  This
change adds an example to that documentation to make it clearer.

[#69514724][resolves #49]
Merge 69514724-java-opts-documentation to master

[Completes #69514724]
Merge remote-tracking branch 'upstream/master'