JDIC integration for RC2 release

Timo already started work on integrating the JDIC project. This currently includes trayicon support with a popup menu and lookup for an appropriate application for the specific mimetype. We also consider to use a better html-viewer instead of the built-in swing JTextPane. But we have to discuss this problem more thoroughly.We will therefore remove the jniwrapper based trayicon support. Nevertheless, jniwrapper will be useful for us. Most probably for Message and Contact import filters and mime contents viewers using win32 applications integrated in the message viewer.