Intervention model refactoring

* adds UserActionLogEntry model to user/models.py
  * wraps user and timestamp info
  * can be extended for more information in the future
* refactors all filtering and accessing on values

compensation/filters.py

@@ -31,7 +31,7 @@ class CompensationTableFilter(InterventionTableFilter):
         """
         if not value:
             return queryset.filter(
-                intervention__recorded_on=None,
+                intervention__recorded=None,
             )
         else:
             return queryset

compensation/tables.py

@@ -34,13 +34,13 @@ class CompensationTable(BaseTable):
         verbose_name=_("Checked"),
         orderable=True,
         empty_values=[],
-        accessor="intervention__checked_on",
+        accessor="intervention__checked",
     )
     r = tables.Column(
         verbose_name=_("Recorded"),
         orderable=True,
         empty_values=[],
-        accessor="intervention__recorded_on",
+        accessor="intervention__recorded",
     )
     e = tables.Column(
         verbose_name=_("Editable"),
@@ -90,7 +90,7 @@ class CompensationTable(BaseTable):
     def render_c(self, value, record: Compensation):
         """ Renders the checked column for a compensation
 
-        checked_on is set by the main object Intervention
+        checked is set by the main object Intervention
 
         Args:
             value (str): The identifier value
@@ -103,9 +103,10 @@ class CompensationTable(BaseTable):
         checked = value is not None
         tooltip = _("Not checked yet")
         if checked:
+            value = value.timestamp
             value = localtime(value)
             checked_on = value.strftime(DEFAULT_DATE_TIME_FORMAT)
-            tooltip = _("Checked on {} by {}").format(checked_on, record.intervention.checked_by)
+            tooltip = _("Checked on {} by {}").format(checked_on, record.intervention.checked.user)
         html += self.render_checked_star(
             tooltip=tooltip,
             icn_filled=checked,
@@ -126,9 +127,10 @@ class CompensationTable(BaseTable):
         checked = value is not None
         tooltip = _("Not registered yet")
         if checked:
+            value = value.timestamp
             value = localtime(value)
             on = value.strftime(DEFAULT_DATE_TIME_FORMAT)
-            tooltip = _("Registered on {} by {}").format(on, record.intervention.recorded_by)
+            tooltip = _("Registered on {} by {}").format(on, record.intervention.recorded.user)
         html += self.render_bookmark(
             tooltip=tooltip,
             icn_filled=checked,