New panel: settings in separate dialogs

[Jasper Huijsmans]

Hi all,

The new panel is coming along nicely. All plugins that I wanted to add 
to a the panel have been added, so I guess I'm more or less ready to 
move it to SVN trunk.

In order to make handling the panel settings more obvious I spit the 
settings into one dialog for properties (and to add/remove panels) and 
one to add items (and move items around).

It would be nice if some people could test the changes and tell me what 
they think. Adding and moving items is now done through drag and drop only.

Suggestions are always welcome.

	Jasper