Löschen von Nachrichten aus dem Archiv implementiert. Dies Löst #2

Signed-off-by: Stephan Richter <s.richter@srsoftware.de>

src/main/java/de/srsoftware/widerhall/data/Post.java

@@ -141,6 +141,10 @@ public class Post {
         return id;
     }
 
+    public MailingList list() {
+        return list;
+    }
+
     public static Post load(String id) throws SQLException {
         var rs = Database.open().select(TABLE_NAME).where(ID,id).compile().exec();
         try {
@@ -161,6 +165,11 @@ public class Post {
                 FILE,filename);
     }
 
+    public void remove() throws SQLException {
+        Database.open().deleteFrom(TABLE_NAME).where(ID,id).compile().run();
+        file().delete();
+    }
+
     public Map<String,Object> safeMap() {
         return Map.of(ID,id,
                 LIST,list.name(),
@@ -186,5 +195,4 @@ public class Post {
     public long timestamp(){
         return timestamp;
     }
-
 }