[front-end, bug-fix] fix EventPublisher.replacePageSubscriptions
[front-end] add scrollbars to widget contents if there is not enough space
[gulp] gulp 'e2e-run-test' and consequently 'test' don't depend on 'build'
[e2e] disable warning about finding multiple 404 btn elements
[e2e] put tests for delete button in a separate block
[e2e] add widget events tests
[e2e,karma,test] remove debugging statements