handle Kiwi 2.x

Results come through like `Test Case '-[NameOfTestFile NameOfTestFile_TextOfContext_TextOfNestedContext_TextOfShould]' passed (0.008 seconds).`, and should come out of `get_test_case_name` like `Text of context, text of nested context, text of should`. Attempts to detect which version of Kiwi they are using, and handle accordingly.

Seems to work on my project, but I'd feel more comfortable if I wrote some unit tests -- would it be wise to move `ReportParser` out of `bin/ocunit2junit` and into its own class?