WebServices: more RedDeer in tests, using ExtendedProblemsView to get problems

Created JAXRSValidatorPreferencePage in order to reimplment JaxRsValidatorTest
with RedDeer.

Using more RedDeer in RESTfulHelper.

Refactored error/warning assertion in RESTfulTestBase.

To some tests was necessary to add sleep() method to ensure that ws validation
reflected expected results to the JAX-RS Explorer