Bug 119331 Library - name space terminology and behavior
During BIRT 2.0 library feature review meeting the following change was decided. - Change the term namespace to 'prefix' - By default use the library name as the prefix ( namespace ); the dialog to input prefix should be prompted only if hte auto generated prefix is not unique.
UI/org.eclipse.birt.report.designer.ui/src/org/eclipse/birt/report/designer/internal/ui/dnd/InsertInLayoutUtil.java
{
		private Object container;
		private CellHandle newTarget;
		public LabelAddRule( Object container )
		{
			this.container = container;
		}
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.birt.report.designer.internal.ui.views.actions.InsertInLayoutAction.InsertInLayoutRule#canInsert()
		 */
		public boolean canInsert( )
		{
			if ( container instanceof SlotHandle )
			{
				container = ( (SlotHandle) container ).getElementHandle( );
			}
			if ( !( container instanceof CellHandle ) )
				return false;
			CellHandle cell = (CellHandle) container;
			
			boolean canInsert = false;
			if ( cell.getContainer( ).getContainer( ) instanceof TableGroupHandle )
			{
				canInsert = true;
			}
			else