refactor(cockpit core): add abstract engine aware

Class org.camunda.bpm.cockpit.service.AbstractEngineAware may be used to
implement engine aware cockpit services and resources.
feat(cockpit): add failure chain query

Added FailureService that provides process definitions with failures

- Test cases altered to use UUID generator
- org.camunda.bpm.cockpit.plugin.test.AbstractCockpitPluginTest integrates
  with engine logging facilities now
- Some test cases are commented out (@Ignore) due to engine bug

Related to CAM-706
Merge branch 'master' of github.com:camunda/camunda-bpm-platform