[FIX] fleet: vehicle cost name field unhacked.
- remove name composition based on vehicle name, date and cost_subtype_id;
instead those fields have been added to the tree view. name field is now just
a related to the vehicle name, but the name field itself does not seem necessary
anymore. Should be checked further.
[FIX] re-enable crawler tests

Move URLCase back out of the test module, otherwise loadTestFromModule
attempts to load it in the usual manner (~URLCase('runTest')). Which does not
work at all, because that's not what URLCase is for.

URLCase extends TestCase to benefit from the TestCase.run infrastructure
(running tests, filling result object, etc...)