179439: Support 3.9.x for a bit longer by building with Java 7
This release was built with Java 7 and compiler settings for Java 6 source/target compatibility. Although the 3.9 is deprecated, this should allow existing customers on 3.9.x some breathing room to upgrade to a more recent release. New releases of 3.9.x will no longer be made with Java 6 (unlike before) so some testing is recommended if you are still on 3.9.x and/or Java 6.