finished rudel textfield

lib/l10n/app_en.arb

@@ -498,9 +498,12 @@
      "@excursion": {
        "description": "no test"
      },
+
      "dateandtime": "Date and Time",
      "@dateandtime": {
        "description": "date and time step header"
      }
 
+     
+
 }