fix(engine/scopeActivity): do not remember current activityInstanceId

This commit extends the hack around the execution tree structure which is not in sync with the activity instance concept:

The current activity instance will be only remembered if:

* the execution is a scope,
* the activity is a scope and
* the behavior of the activity is a CompositeActivityBehavior

related to CAM-1883
feat(integration-test): add protractor prototype
feat(e2e-tests): Add basic test setups

related to #CAM-1642
-Add start scripts for camunda-bpm-platform, webdriver, protractor
-Add test configurations for Admin, Tasklist and Cockpit
-Add test procedures for Admin, Cockpit and Tasklist
feat(integrtation-test): add semantic attributes

- add semantic attributes to increase accessibility of elements
- expand test procedures for all web apps
improve(cockpit/build): remove the sem- attrs on the production files
chore(integration-test): move protractor tests

-relocate protractor tests to folder e2e
-extend test coverage
Merge branch 'CAM-1628-ui-scenario-tests' of github.com:camunda/camunda-bpm-platform into CAM-1628-ui-scenario-tests