Project 4.15.6

Builds packages for JMRI release 4.15.6

These packages require Java 8 (or newer) to run.

These are not official releases. Only packages downloaded from jmri.org are official releases.

This job runs 'ant clean warnings tests-warnings headlesstest checkPropertiesFiles javadoc packages sign-macosx'.

Build properties set:

• release.official=true
• release.is_branched=true