Remove debugging code.

Change-Id: If3a64a6914ae8ce2521c85766df6f733a13ca7e1
Reviewed-on: https://code.wireshark.org/review/5926
Reviewed-by: Gerald Combs <gerald@wireshark.org>
Qt: Use an accordion frame in the welcome screen.

Place the recent files list in an accordion frame so that showing and
hiding is more visually smooth.

Change-Id: Ifdc534a33aa9f93949c9f919cfe0765fbfcde750
Reviewed-on: https://code.wireshark.org/review/5924
Reviewed-by: Gerald Combs <gerald@wireshark.org>