feat(breadcrumbs): Show breadcrumbs in cockpit

- Now breadcrumbs will be shown in cockpit
- It shows the current selected process definition
- If drill down to a specific process instance, then the breadcrumbs
  contains the corresponding process definition and the current selectd
  process instance. In case of a called process instance, it is possible
  to expand to show the call hierarchy of process instance.
- if process instance could not be loaded, then the start page with a
  corresponding notification will be shown.

related to CAM-913, CAM-1000
Merge branch 'master' of github.com:camunda/camunda-bpm-platform