The config GUI supports special configuration widgets/dialogs for sub-trees of the config. Currently, these are hard-coded into the config gui.

The config gui should be modified to have a plugin mechanism similar Fawkes itself, such that a plugin can be self-contained and bring its own configuration GUI plugin. Additionally domain dependent code does not need to be copied between branches, as it happens at the moment.

For the plugin GUI the API should be slightly modified, such that instead of a dialog a widget is returned. This gives flexibility on the GUI side to use dialogs or embed the widget into the main window if desirable. All existing plugins should be loaded at startup, making the loading procedure a lot easier.