Unnable to enter expense with decimals when display setting to hide decimals

[maraf]

If user sets to display decimals to 0, they can't enter expense with decimals.

The typical use case is "I want no decimals for Kč, but when entering expense in Eur, I want to enter decimals".

We should move the user property to a currency based setting, allowing users to define display decimals per currency

I think we should go a step further and allow to enter decimals even for currency that is displaying without decimals.