feat: Add FWAV, INFO, ITAV, ITBD and XPCD balance types

[DannyvdSluijs]

This PR solves #156

[PowerKiKi]

Looks like a good start, but we miss unit tests for it. You can add a new pair of xml and json files in test/data, to test all cases at once.

[DannyvdSluijs]

Thanks for the feedback. I've added test.

One think to be cautious are the other tests that started to fail due to unsupported balance types also being in those files.
I think it also showed a different problem as the test/data/camt052.v6.xml file had a balance with a DtTm element (In the Balance type the Dt field is of a type DateAndDateTimeChoice. For the mentioned file there was a DtTm sub element which isn't supported in code resulting in the test always failing as it was doing a fallback to now when creating the DateTime object.
For the scope of this PR I opted to correct the regression file to match the code.

Let me know what you think and if any changes are needed.

[PowerKiKi]

Thank you !