ARQGRA-266: bug with jquery locators and waitings fixed

Thr problem was the following scenario:

1. an action reloading page started performing,
2. waiting started,
3. JQuery page extension was installed,
4. page reloaded (all page installed page extensions dropped),
5. page extension mechanism tried to check whether the JQuery extension
   is instaled -> FAIL

The solution  is to use @JavaScript interfaces instead of raw page extensions.
The @JavaScript interfaces can handle this interleaving since ARQGRA-262.