Bug 143173 No error for recursive including when exporting a report to a library
Steps to reproduce: 1.New a library named "Lib", add a lable in it 2.New a report, extends Lib.label 3.Export the report, choose target library "Lib" Expected result: Error to warn the recursive including Actual result: The target library includes itself without error
model/org.eclipse.birt.report.model/src/org/eclipse/birt/report/model/util/ModelUtil.java
* BIRT. Currently, BIRT only supports UTF-8 encoding.
	 * 
	 * @param inputStream
	 *            the input stream to check
	 * @param fileName
	 *            the design file name
	 * @return the signature from the UTF files.
	 * @throws IOException
	 *             if errors occur during opening the design file
	 * @throws SAXException
	 *             if the stream has unexpected encoding signature
	 */
	public static String checkUTFSignature( InputStream inputStream,
			String fileName ) throws IOException, SAXException
	{
		
		
		String encoding = UnicodeUtil.checkUTFSignature( inputStream );
		if ( encoding != null && !UnicodeUtil.SIGNATURE_UTF_8.equals( encoding ) )
		{
			Exception cause = new DesignParserException(
					DesignParserException.DESIGN_EXCEPTION_UNSUPPORTED_ENCODING );
			Exception fileException = new DesignFileException( fileName, cause );
			throw new SAXException( fileException );
		}
		return encoding;
	}
	/**
	 * 
	 * Performs property name sorting on a list of properties. Properties