Add error messages to translation files

client/public/locales/de/translation.json

@@ -13,6 +13,11 @@
         "labelEmail": "Deine Email",
         "labelName": "Dein Name",
         "labelAnnotations": "Anmerkungen (optional)",
-        "buttonBookBoat": "Boot jetzt buchen!"
+        "buttonBookBoat": "Boot jetzt buchen!",
+        "messages": {
+            "required": "'{{val}}' wird benötigt",
+            "invalidTime" : "Bitte trage eine gültige Uhrzeit für '{{val}}' ein (hh:mm)",
+            "invalidEmail" : "Bitte trage eine gültige Email ein"
+        }
     }
 }
\ No newline at end of file

client/public/locales/en/translation.json

@@ -13,6 +13,11 @@
         "labelEmail": "Your Email",
         "labelName": "Your Name",
         "labelAnnotations": "Annotations (optional)",
-        "buttonBookBoat": "Book this boat!"
+        "buttonBookBoat": "Book this boat!",
+        "messages": {
+            "required": "'{{val}}' is required",
+            "invalidTime" : "Please enter a valid time for '{{val}}' (hh:mm)",
+            "invalidEmail" : "Please enter a valid mail address"
+        }
     }
 }
\ No newline at end of file