Enable reproducible builds by suppressing date comment in properties

[joschi]

Context

The native java.util.Properties class in Java will add a comment in each properties file with the timestamp when the file was generated, which prevents projects implementing reproducible builds.

This change set replaces the usage of java.util.Properties and the custom order-preserving wrapper around it with the java-ordered-properties project, which prevents writing the timestamp comment and still retains a reproducible order in the properties files.

Fixes #472

Contributor Checklist

• Added relevant integration or unit tests to verify the changes
• Ensured that tests pass locally: mvn clean package
• Ensured that the code meets the current checkstyle coding style definition: mvn clean verify -Pcheckstyle -Dmaven.test.skip=true -B

[TheSnoozer]

Hi, sorry for the delay (again). Thanks for taking care of this and your contribution! Also a great shout-out for your contribution to etiennestuder/java-ordered-properties#4!

Changes look good to me. I'm going ahead and merge :-)