Bug 167545 Copy a cascading parameter group and paste it to another parameter group causes an exception thrown
Steps to reproduce: 1.Copy a cascading parameter group using short cut key "Ctrl+x"/"Ctrl+c", or choosing context menu "Cut"/"Copy"; 2.Paste it to another parameter group using short cut key "Ctrl+v", or choosing context menu "Paste"; Expected result: The source one is pasted in the destination. Actual result: An exception thrown org.eclipse.birt.report.model.api.command.ContentException: The Cascading Parameter Group("Source") is not allowed in the slot (parameters) of Parameter Group("Destination").
UI/org.eclipse.birt.report.designer.core/src/org/eclipse/birt/report/designer/util/DEUtil.java
* 
	 * @param value
	 *            given string value
	 * @return [number][other]
	 */
	public static String[] splitString( String value )
	{
		String[] spt = new String[2];
		if ( value != null )
		{
			for ( int i = value.length( ); i > 0; i-- )
			{
				if ( isValidNumber( value.substring( 0, i ) ) )
				{
					spt[0] = value.substring( 0, i );
					spt[1] = value.substring( i, value.length( ) );
					break;
				}
			}
			if ( spt[0] == null && spt[1] == null )
			{
				spt[1] = value;
			}
		}
		return spt;
	}
	/**
	 * If given value if null, return an empty string, or return itself.
	 * 
	 * @param value