KRDC 'Quit' behaviour is not consistent when the 'Enable system tray icon' option is ticked

[Alvin]

Steps to reproduce:
- Enable tray icon (Settings > Configure KRDC > General)
- Fullscreen mode: 'Quit application' button closes KRDC
- Windowed mode: Quit button (X in top right) minimizes KRDC to tray

What is expected:
- An extra option 'Hide to tray on close button'.
- close to tray also working when in Fullscreen mode.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: krdc 4:4.13.0-0ubuntu1
ProcVersionSignature: Ubuntu 3.13.0-30.54-generic 3.13.11.2
Uname: Linux 3.13.0-30-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.14.1-0ubuntu3.2
Architecture: amd64
CurrentDesktop: KDE
Date: Thu Jul 3 13:58:26 2014
InstallationDate: Installed on 2014-06-28 (4 days ago)
InstallationMedia: Kubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.1)
SourcePackage: krdc
UpgradeStatus: No upgrade log present (probably fresh install)