New GUI for configuration & Instllation

This release introduces the new GUI with various features:

• New: The signer can now be configured through the GUI instead of manual XML editing
• New: Installation, Update and Uninstall is now done by a simple click within GUI
• New: Private key support (PEM, DER, XML)
• New: Set agent priority through GUI
• New: View Agent event log within GUI
• Fix: Removed RecipientRule and SenderRule causing trouble when signing emails

Unfortunately we had to change the configuration format. Therefore you need to reconfigure the agent using the GUI to restore your previous state