[DF-291] Add IsOnScreen() method to LUA api.
Merge branch 'development' of https://github.com/abaradulkin/dava.framework into development
Merge branch 'development' of https://github.com/dava/dava.framework into development
Merge pull request #250 from abaradulkin/development

DF-291 fixes in autotesting lua api
[DF-291] Fix IsVisible()
Merge branch 'development' of https://github.com/abaradulkin/dava.framework into development
Merge branch 'development' of https://github.com/dava/dava.framework into development