[PAXEXAM-665] Prepare and stage reactor for each test class with
TestNG driver to apply per-class configuration
[PAXEXAM-665] simplified exception handling
[PAXEXAM-665] use TestNG 6.8.8
[PAXEXAM-666] Upgrade to Logback 1.1.2
[PAXEXAM-667] Upgrade to Tomcat 8.0.14
[PAXEXAM-667] Adapt to changed Tomcat API