improved archive: storage dir cannow be configured. also, mails are now displayed in send-time order

src/main/java/de/srsoftware/widerhall/Configuration.java

@@ -59,6 +59,7 @@ public class Configuration {
         dbFile();
         baseUrl();
         serverPort();
+        archiveDir();
         return this;
     }
 
@@ -92,6 +93,13 @@ public class Configuration {
         return this;
     }
 
+    public File archiveDir() {
+        var locations = locations();
+        if (!locations.containsKey(ARCHIVE)) locations.put(ARCHIVE, String.join(File.separator,baseDir(),"archive"));
+        return new File((String) locations.get(ARCHIVE));
+    }
+
+
     public int serverPort() {
         if (!data.containsKey(PORT)) data.put(PORT,80L);
         var o = data.get(PORT);
@@ -107,4 +115,5 @@ public class Configuration {
     public File file() {
         return file;
     }
+
 }