EMA

* fixes created timestamp in detail views where modified needs to be displayed
* adds fallback timestamp if data has not been edited, yet --> show created timestamp
* fixes bug where deleting of certain data didn't redirect to the index view
* adds quality_check() method for EMA, needed for recording
* adds all functions which are provided for compensations to EMA
* adds/updates translations

locale/de/LC_MESSAGES/django.po

@@ -1276,7 +1276,7 @@ msgstr "Filter anwenden"
 
 #: templates/log.html:7
 msgid "Timestamp"
-msgstr ""
+msgstr "Zeitpunkt"
 
 #: templates/log.html:13
 msgid "User"