feat: add help for tags

Author: Tienisto

lib/language/strings/de.dart

@@ -18,6 +18,7 @@ const Map<String, dynamic> de = {
     'selectPlace': 'Bitte wähle eine Location aus:',
     'unknown': 'Unbekannt',
     'comment': 'Kommentieren',
-    'tags': 'Tags'
+    'tags': 'Tags',
+    'tagsHelp': 'Tags mit Leerzeichen trennen'
   }
 };

lib/language/strings/en.dart

@@ -18,6 +18,7 @@ const Map<String, dynamic> en = {
     'selectPlace': 'Please select a location:',
     'unknown': 'Unknown',
     'comment': 'Comment',
-    'tags': 'Tags'
+    'tags': 'Tags',
+    'tagsHelp': 'Separate tags with spaces'
   }
 };

lib/routes/comment_page.dart

@@ -156,6 +156,11 @@ class _CommentPageState extends State<CommentPage> {
                       focusedBorder: OutlineInputBorder(borderSide: BorderSide(color: Colors.grey, width: 2))
                     ),
                   ),
+                  SizedBox(height: 10),
+                  Align(
+                    alignment: Alignment.centerRight,
+                    child: Text(t('placeInfo.tagsHelp'), style: TextStyle(color: Colors.grey, fontStyle: FontStyle.italic)),
+                  ),
                   SizedBox(height: 50),
                   FlatButton(
                     shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(50.0)),