Changed class and method names for failing assertions tests.
Added query creation helpers automatically narrowing queries for all existing *Assert classes.
Adapted and extended a few comments.
Added methods to be able to retrieve a refreshed version of actual object under test.
Added processDefinitionQuery() helper method - unnarrowed and 'narrowed' to the needs of specialised *Assert classes.
Reformatted code of ProcessEngineAssertions class.
Added processDefinitionQuery() helper method.
Refactored JobAssert tests and adapted them to fit to the pattern of the other tests.
Made checking for AssertionError flexible, in order to potentially check for other exceptions, too.
Added test to check for ProcessEngineException in case the request for a chained TaskAssert does not deliver exactly one task.