Not able to enter transaction with small fee

[markokocic]

Describe the bug I wanted to enter a transaction which has a small fee amount,.

To Reproduce Steps to reproduce the behavior:

1. Create a new "Sell" transaction in depot.
2. Enter "0,00000004" as an amount of BTC, enter "0,0017" as an aomunt in EUR
3. Try to save a transaction, which is not possible. Looks like PP requires at leas 0,01 EUR as an amount.

Another issue is that, for other transaction, EUR amounts are limited automatically rounded to 2 digits. This is an issue since, e.g. Kraken works with 4 digit EUR amount for trades and fees. Working with rounded amount leads to wrong calculation.

Expected behavior PP should let me save a transaction using as many decimal places as entered in the input form.

Note: In formatting settings number of digits for shares is set to 8, and for calculated courses to 4.

Desktop (please complete the following information):

• OS: Windows
• Version 0.56.0 (Nov. 2021)