Clean up OdtDocument cursor position tests

Make OdtDocument cursor position tests more granular in how they are reported. This makes it easier to troubleshoot individual failing tests as the individual test is more specific.

* Extend core test runner to cope with test names containing angle brackets
* Verify the number of steps vs. expected number of cursor positions
* Remove doc length check for non-changing variables
* Report one test per cursor position document fragment
Mh, okay. I would have made the escaping catch here a bit more broad given that examples show some non-[azAZ] chars to expect, but if you think this will soon be replaced and until then should just be hacked on case-by-case, well, there are more important things to discuss about :)
So please go with this and rebase and merge :hamster: