RF-12950: introduced integration tests for showcase

- added surefire plugin to set system variable
- added a integration package with one dummy test

RF-12950 move first pack of tests

RF-12950 move second pack of tests
RF-12950 moved showcase focus test
RF-13766 Move classes ElementIsFocused and FocusRetriever to build-resources
RF-12950: tests fixing or putting to @Ignore if they are not stable enough
RF-12950: Some tests added to Smoke @Category

-they run for 1 minute
RF-12950: Introduced getters for all WebElements & PF

-Graphene support to the future accessing WebElements and PF from within Page Objects only via getters methods