Eco Account deduction

* adds deductable_surface to EcoAccount model to provide an easy way to change the deductable amount from an account -> depends on external funding e.g. with AktionBlau or similar
* adds overview of deducted and deductable volume to detail view
* adds check to eco account model, so the deductable_surface can never be larger than the total amount of after_state surface sum
* adds german formating for python logic based number formating
* adds/updates translations

konova/utils/general.py

@@ -0,0 +1,21 @@
+"""
+Author: Michel Peltriaux
+Organization: Struktur- und Genehmigungsdirektion Nord, Rhineland-Palatinate, Germany
+Contact: michel.peltriaux@sgdnord.rlp.de
+Created on: 17.09.21
+
+"""
+
+
+def format_german_float(num) -> str:
+    """ Writes a float into a string based on german float notation
+
+    10000.000  --> "10.000,00"
+
+    Args:
+        num (float): The number
+
+    Returns:
+        num (str): The number as german Gleitkommazahl
+    """
+    return format(num, "0,.2f").replace(",", "X").replace(".", ",").replace("X", ".")