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- Cleanup
- Add more units
[133](https://github.com/juhasch/PhysicalQuantities/pull/133)
[juhasch](https://github.com/juhasch)
- Add currencies and retrieve exchange rates from `forex-python`
[134](https://github.com/juhasch/PhysicalQuantities/pull/134)
[juhasch](https://github.com/juhasch)
- Fix ReadTheDocs build
Unreleased (aka. GitHub master)
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