Set development version 2.2-SNAPSHOT
Update license text
Set next development version 2.2-SNAPSHOT
Update to next development version of prefdialog-public 2.2-SNAPSHOT
Add children panel

The panel will contains a tree for the children values of the
preferences.
Add a factory for the children list panel
Add method to select the node with the child object

The panel will keep track of added child nodes.
Add getter of the currently selected child object
Add getter/setter for the children notes renderer
Add children panel that have the children list and the child panel
Change the panel prefix to avoid the same name for two panels.
Remove the name constants for implementation internal components

The tree and scroll pane is an implementation of many possible for
children list panel.
Add factory for children panel, add test
Fix split, Set horizontal split
Add method to set the child panel
Set empty panel for initial child panel

To set the split between the children list and the child panel.
Remove the not needed test
Rework preference dialog using children panel
Add border and gaps for buttons
Rename the panel name postfix constant to PANEL_NAME_POSTFIX

So the meaning is in the name, it is a postfix for the names.