feat(cockpit/engine): failed jobs cockpit plugin
- Implement a new cockpit plugin to show the last failed jobs in camunda bpm engine, to be used on start page of cockpit.
- Retrieve the latest failed jobs using camunda Rest API, http://docs.camunda.org/latest/api-references/rest/#job-get-jobs (Parameter withException = true).
- Create hyperlinks to navigate the oprator to a live view of the process instance.
- Display exception messages for those which has it, with a hyperlink to show the whole stacktrace. 
- Use camunda paginator component to provide paging feature.
- Show tooltip like help-texts, providing some helpful tips and also the process name in JobId column.
related to #CAM-1901