Bug 38317 Add getter/setter templates.
Add template support to the code generation pref panel for getter and setter method bodies.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/preferences/CodeTemplateBlock.java
private class CodeTemplateAdapter implements ITreeListAdapter, IDialogFieldListener {
		private final Object[] NO_CHILDREN= new Object[0];
		public CodeTemplateAdapter(CodeTemplates templates) {
		}		
		public void customButtonPressed(TreeListDialogField field, int index) {
			doButtonPressed(index, field.getSelectedElements());
		}
			
		public void selectionChanged(TreeListDialogField field) {
			List selected= field.getSelectedElements();
			field.enableButton(IDX_EDIT, canEdit(selected));
			field.enableButton(IDX_EXPORT, !selected.isEmpty());
			
			updateSourceViewerInput(selected);
		}
		public void doubleClicked(TreeListDialogField field) {
			List selected= field.getSelectedElements();
			if (canEdit(selected)) {