Currency hotfixes

[zorun]

Hardcode list of currencies, and temporarily disable some currency operations to prevent crashes.

Here is what is disabled:

• setting or changing the default currency on an existing project
• adding or editing a bill with a currency that differs from the default currency of the project

Adjust and skip tests as necessary.

The real fix will come after #1232 is discussed

[zorun]

I'd like to release version 6.1.1 as soon as this is merged (which means really soon)

[zorun]

You mean simulating the exception that would be raised by the API call? It's a good idea, that would have allowed us to catch this way earlier. But I'm not motivated enough to do this now...

[almet]

You mean simulating the exception that would be raised by the API call? It's a good idea, that would have allowed us to catch this way earlier. But I'm not motivated enough to do this now...

I understand, especially as it's a quick fix for an emergency release. Let's move on then, I won't have the time to add it either.

Thanks again for doing that!

[zorun]

Thanks for the review! I will make the release now.