zlibsvm-2.0.3

Changes

• updates libsvm to 3.25 (was 3.24), changelog: https://www.csie.ntu.edu.tw/~cjlin/libsvm/log
• updates commons lang3 to 3.12.0 (was 3.11), changelog: https://commons.apache.org/proper/commons-lang/changes-report.html#a3.12.0

Minor Changes

• introduces version checking for build env