i2psnark: Fix autostart for torrent files copied into the dir

Use Collator for case-insensitive sort
Use Exception.getLocalizedMessage()
Prevent duplicate torrent starts
Don't write debug info to wrapper log
Increase max piece size
Navbar cleanup

apps/i2psnark/java/src/org/klomp/snark/Snark.java

@@ -552,6 +552,8 @@ public class Snark
    * @throws RuntimeException via fatal()
    */
   public synchronized void startTorrent() {
+      if (!stopped)
+          return;
       starting = true;
       try {
           x_startTorrent();